Installing computer systems and networks
Plan and prepare for installation
Information Sheet No 1.1-1 Safety procedures
Learning objective: Upon completion of this chapter, you will be able to answer the following questions: 1. Identify 5S of good housekeeping2. 2. Recognize safety rules and regulations3. 3. Plan installation of computer systems and networks according to industry standards SAFETY PROCEDURE is a common task. It is a general knowledge in our workplace. In most cases, one must be trained to apply safety procedures in particular place or in an environment of a certain work, such as factory where there is heavy machineries, electronics and high voltage facilities. SAFETY PROCEDURES may be able to promote a great stability of accompany, to ensure safety of their own products, their facilities and most especially their personnel during and after work responsibility. Therefore, it is our goal and responsibility as a worker, in any field of our skills and even in our great profession, to have these skill and knowledge for future application in our workplace. 5S OF GOOD HOUSE KEEPING
S- sieri /Sort o Take out unnecessary items and dispose S- seiton /Systematize o Arrange necessary items in good order for use S- seiso/ Sweep o Clean your workplace S- seiketsu/ Sanitize o Maintain high standard of housekeeping S- Shitsuke/ Self- discipline o Do things spontaneously without being told
GENERAL SAFETY PRECAUTIONS 1. Remove power from the circuit or equipment before working on it.
2. Remove and replace fuses only after the power to the circuit has been de energized. 3. Make sure all equipment is properly grounded. 4. Use extreme caution when removing or installing batteries containing acid. 5. Use cleaning fluids only in well- ventilated spaces. 6. Dispose of cleaning rags and other flammable materials in tightly closed metal containers. 7. In case of an electrical fire, de energize the circuit and report it immediately to the appropriate authority. HIGH VOLTAGE SAFETY PRECAUTIONS 1. Consider the result of each act. 2. Keep away from live circuits. 3. Do not work alone. 4. Do not tamper with interlocks. 5. Do not ground yourself. 6. Never energize equipment in the presence of water leakage. PERSONAL SAFETY PRECAUTIONS 1. Work only in clean dry areas. 2. Do not wear loose or flapping clothing. 3. Wear only nonconductive shoes. 4. Remove all rings, wristwatches, bracelets, ID chains and tags, and similar metal items. 5. Do not use bare hands to remove hot parts. 6. Use a shorting stick to remove high voltage charges on capacitors. 7. Make certain that the equipment being used is properly grounded. 8. Remove power to a circuit prior to connecting alligator clips. 9. When measuring voltages over 300 volts, do not hold the test probes.
General Safety Safe working conditions help prevent injury to people and damage to computer equipment. A safe workspace is clean, organized, and properly lighted. Everyone must understand and follow safety procedures. Follow the basic safety guidelines to prevent cuts, burns, electrical shock, and damage to eyesight. As a best practice, make sure that a fire extinguisher and first-aid kit are available in case of fire or injury. Poorly placed or unsecured cables can cause tripping hazards in a network installation. Cables should be
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There are certain procedures you should follow when you are installing items in your system. Below is information to avoid damage to your system or/and yourself.
Before entering the computer, move computer off the carpet (for static purposes). If you’re not able to then try not to move on the carpet to keep the static from building. Disconnect all cables including power cord. I can't stress this enough. Remove the power cord, monitor, keyboard, mouse, phone line, network cable, speakers, printer, scanner, USB cables, cable modem, DSL modem and anything else that is connected. (it should look similar to the picture below) With everything disconnected, push the power button for 5 seconds. (with power cord disconnected). The computer can store power even with the power cord disconnected. Pushing the power button drains that power (only if the power cord is disconnected). VERY IMPORTANT!!! Touch something metal on the case of the system to release any static build up in your body. Computers are the best dust collectors. Do not blow on the dust with your breath. Your breath has moisture and electronics hate moisture. If you want to clean the inside of the system of dust, use compressed air that is designed for electronics. While using the compressed air, do not hold down the button. Not only will they can get cold, moisture will also form. Use quick short bursts. When handling parts, do not touch the bronze teeth. Hold the parts on the edges if at all possible. If you are troubleshooting noise issue, some people will stick a pencil or other objects in the fan to stop the fan from turning to see if the noise goes away. DON'T DO THAT! The fan might shatter the pencil, cause a fire, cause electrical shock or short. If you disconnect the cable that goes to the processor fan to check for noise, do not leave system on for long with it disconnected. Be careful while inside system, the system has sharp edges. Never put your hands inside system when the system is either plugged in or turned on. Some computer desks have a compartment that you can put your computer in. Make sure that compartment is well ventilated. If it is not
ventilated, it can fry the system. If it is not well ventilated, you can drill holes in the desk to give it ventilation, or you can install a small fan in the desk that will circulate air. Do not connect or disconnect cables while the system or device is turned on. (unless it is USB. USB can be disconnected or connected while system is on). Equipment can be damaged by this. ****VERY VERY IMPORTANT NOTE****
If you have access to your personal files, make sure they are backed up before tinkering with the system. Sometimes there can be more than one issue and one of the issues may not show till you start tinkering with the system. For example, I have seen a hard drive be bad but it works as long as the system is on. However when you turn the system off, the hard drive doesn't work anymore. Once that happens, you can't get access to your files.
Electrical Safety Follow electrical safety guidelines to prevent electrical fires, injuries, and fatalities in the home and the workplace. Power supplies and CRT monitors contain high voltage. CAUTION Do not wear the antistatic wrist strap when repairing power supplies or CRT monitors. Only experienced technicians should attempt to repair power supplies and CRT monitors. Some printer parts become hot during use, and other parts might contain high voltage. Check the printer manual for the location of high-voltage components. Some components retain a high voltage even after the printer is turned off. Make sure that the printer has had time to cool before making the repair. Electrical devices have certain power requirements. For example, AC adapters are manufactured for specific laptops. Exchanging power cords with a different type of laptop or device may cause damage to both the AC adapter and the laptop. Procedures to Protect Equipment and Data Replacing equipment and recovering data is expensive and time consuming. This section identifies potential threats to systems and describes procedures to help prevent loss and
damage. ESD and EMI Electrostatic discharge (ESD), harsh climates, and poorquality sources of electricity can cause damage to computer equipment. Follow proper handling guidelines, be aware of environmental issues, and use equipment that stabilizes power to prevent equipment damage and data loss. Static electricity is the buildup of an electric charge resting on a surface. Electrostatic discharge (ESD) occurs when this buildup jumps to a component and causes damage. ESD can be destructive to the electronics in a computer system. At least 3000 volts of static electricity must build up before a person can feel ESD. For example, static electricity can build up on you as you walk across a carpeted floor. When you touch another person, you both receive a shock. If the discharge causes pain or makes a noise, the charge was probably above 10,000 volts. By comparison, less than 30 volts of static electricity can damage a computer component. ESD can cause permanent damage to electrical components. Follow these recommendations to help prevent ESD damage:
Keep all components in antistatic bags until you are ready to install them. Use grounded mats on workbenches. Use grounded floor mats in work areas. Use antistatic wrist straps when working on computers.
Electromagnetic interference (EMI) is the intrusion of outside electromagnetic signals in a transmission media, such as copper cabling. In a network environment, EMI distorts the signals so that the receiving devices have difficulty interpreting them. EMI does not always come from expected sources, such as cellular phones. Other types of electric equipment can emit a silent, invisible electromagnetic field that can extend for more than a mile (1.6 km). There are many sources of EMI:
Any source designed to generate electromagnetic energy Man-made sources like power lines or motors Natural events such as electrical storms, or solar and interstellar radiations
Wireless networks are affected by radio frequency interference (RFI). RFI is caused by radio transmitters and other devices transmitting in the same frequency. For example, a cordless telephone can cause problems with a wireless network when both devices use the same frequency. Microwaves can also cause interference when positioned in close proximity to wireless networking devices. Climate affects computer equipment in a variety of ways:
If the environment temperature is too high, equipment can overheat. If the humidity level is too low, the chance of ESD increases. If the humidity level is too high, equipment can suffer from moisture damage.
Power Fluctuation Types Voltage is the force that moves electrons through a circuit. The movement of electrons is called current. Computer circuits need voltage and current to operate electronic components. When the voltage in a computer is not accurate or steady, computer components might not operate correctly. Unsteady voltages are called power fluctuations. The following types of AC power fluctuations can cause data loss or hardware failure:
Blackout: Complete loss of AC power. A blown fuse, damaged transformer, or downed power line can cause a blackout. Brownout: Reduced voltage level of AC power that lasts for a period of time. Brownouts occur when the power line voltage drops below 80 percent of the normal voltage level. Overloading electrical circuits can cause a brownout. Noise: Interference from generators and lightning. Noise results in poor quality power, which can cause errors in a computer system. Spike: Sudden increase in voltage that lasts for a short period and exceeds 100 percent of the normal voltage on a line. Spikes can be
caused by lightning strikes, but can also occur when the electrical system comes back on after a blackout. Power surge: Dramatic increase in voltage above the normal flow of electrical current. A power surge lasts for a few nanoseconds, or onebillionth of a second.
Power Protection Devices To help shield against power fluctuation problems, use power protection devices to protect the data and computer equipment:
Surge suppressor: Helps protect against damage from surges and spikes. A surge suppressor diverts extra electrical voltage that is on the line to the ground. Uninterruptible power supply (UPS): Helps protect against potential electrical power problems by supplying a consistent level of electrical power to a computer or other device. The battery is constantly recharging while the UPS is in use. The UPS provides a consistent quality of power when brownouts and blackouts occur. Many UPS devices can communicate directly with the computer operating system. This communication allows the UPS to safely shut down the computer and save data prior to the UPS losing all electrical power. Standby power supply (SPS): Helps protect against potential electrical power problems by providing a backup battery to supply power when the incoming voltage drops below the normal level. The battery is on standby during normal operation. When the voltage decreases, the battery provides DC power to a power inverter, which converts it to AC power for the computer. This device is not as reliable as a UPS because of the time it takes to switch over to the battery. If the switching device fails, the battery cannot supply power to the computer.
CAUTION UPS manufacturers suggest never plugging in a laser printer to a UPS because the printer could overload the UPS.
Information Sheet No 1.1-2 Basic terms, concepts, functions and characteristics of PC hardware components
Learning objective: Upon completion of this module, the students will be able to 1. Identify different parts of the computer. 2. Define computer terms
Basic Computer Terms Address
– a number that represent a unique location in memory
ALU – Arithmetic Logic Unit, part of a microprocessor. It does all arithmetic functions and calculation in the CPU. ASCII – American Standard Code for Information Interchange, code representing the character symbols possible for specific hexadecimal codes. BIOS – Basic Input/Output System, the part of the operating system that controls the input and output functions. Bit
– the single smallest unit of data in a computer.
Board – a shortened reference to a printed circuit board or the insulated surface on which circuit components are mounted and soldered in place. Boot
– a term meaning to load DOS or an operating system.
Byte
– comprised of 8 bits to form a word
Character – the equivalent meaning of byte formed. Chip – a complete electronic circuit which may contain miniature resisters, transistors, diodes, and related circuitry all integrated into a miniature silicon base and mounted in a common housing. Computer – an electronic device designed to make rapid, accurate computations from data programmed into it.
Control Unit – decodes each instruction that enters the computer. It then generates the necessary pulses to carry out the functions specified. CP/M – Control Program for Microprocessors, the first operating system developed for microcomputers. CPU – Central Processing Unit, the heart of a system. It controls all data transfer and devices in a microcomputer system. DMA – Direct Memory Access, data transfer involving large blocks of information directly between the memory and disk drives. DMA is controlled by other processors which speeds up data transfer and unloads the central processors of this function. DOS – Disk Operating System, a software program used to set certain parameters involving the operation of the computer system. To start it up especially data transfer and the disk drives. Hardcopy – a print out or a visual copy on paper. I/O – short for Input/Output, any operation or device that sends or receives data from or to the CPU. IC – short for Integrated Circuit, building blocks of a computer system or other electronics devices comprising many electronics parts such as transistors, resistors, etc. in a single package. Interrupt – an input signal to the processors that sets the order to initialize all system devices for operation. Kilo
– prefix which means 1,000 units
LSI – Large Scale Integration, describes the intensity of integration commonly used in microprocessors, comprising many ICs. Mainframe computers – the largest and most expensive computers designed specifically to serve business, industry, and government in applications that require mass storage and fast retrieval.
Example: Banks, airlines, and the Internal Revenue Service use mainframe Computers Mega
– prefix which means 1,000,000 units
Memory – the part of a computer that stores vital information for the computer’s operation. Microcomputers – the smallest and least expensive computers, designed for desktop or portable use by an individual at home, yet versatile enough for applications in business, industry, and government Example: Microcomputers enjoyed early popularity in the home for both educations and playing electronic games, but as microcomputers expand in powers such as multi-tasking and multi-user applications, their use in business and industry increases. Microprocessor – the arithmetic logic unit, registers, and timing and decoding circuitry usually contained in a single integrated circuit that controls computer activities. Minicomputers – medium-sized and medium-priced computers that rival the storage capacity and operating speed of smaller main-frames, and are used in business, industry, and government where they perform mostly dedicated or single-task activities. Example: Food processors, laboratories, and hospitals use minicomputers Peripheral – any device or accessory such as a disk drive, printer, modem, or video display added to a microcomputer to provide increased capacity for handling, storing, or presenting data. POR – Power On Reset, or power on routing, term to describe the sequence of operations of a machine during power up. Programs – contain the instructions that tell the computer what to do. It is a sequential set of instructions to solve a particular problem. Prototype – the first of its kind, the original from which later models are
patterned. RAM – Random Access Memory, data can either be read from or written to (read/write). Read
– to get data from a device.
Reset – a short pulse during power up of perform control function in computer, used to initialize all system devices for operation. ROM – Read Only Memory, data can only be read from this type of memory. It cannot be altered and contains the basic operating instruction of the computer.
Unix – the operating system used by the IBM PC, having a more powerful command structure and greater expandability than CP/M Write – to put data into a device. Computer Acronyms
ACE - Asynchronous Communication Element ACPI - Advance Configuration and Power Interface ADC - Analog-to-Digital Converter ADO - Active Data Object ADSL - Asymmetric Digital Subscriber Line (variant of DSL) AGP - Accelerated Graphics Port ALU - Arithmetic Logic Unit AMR - Audio Modem Riser API - Application Programming Interface ASCII - American Standard Code for Information Interchange ATA - Advanced Technology Attachment BCD - Binary Coded Decimal BEDO RAM - Burst EDORAM BIOS - Basic Input Output System BIU - Bus Interface Unit CGI - Common Gateway Interface CAD - Computer – Aided Design
CMOS CPU CRT DMA DTE DDR DIMM DLL DNS DOS DRAM DSL DVD EDO EPROM FAT FRAM FDD FSB FTP GIF GPRS GSM GUI HDD HTML HTTP IC IBM ICT IDE I/O IP IRQ IT ISA JFET
- Complementary Metal Oxide Semiconductor - Central Processing Unit - Cathode Ray Tube - Direct Memory Access - Data Terminal Equipment - Double Data Rate - Dual Inline Memory Module - Dynamic Link Library - Domain Name System - Disk Operating System - Dynamic Random Access Memory - Digital Subscriber Line - Digital Versatile Disc - Enhanced Data Output - Erasable Programmable Read Only Memory - File Allocation Table - Ferro-Magnetic RAM - Floppy Disk Drive - Front Side Bus - File Transfer Protocol - Graphics Interchange Format - General Packet Radio Service - Global System for Mobile Communication - Graphical User Interface - Hard Disk Drive - Hypertext Markup Language - Hypertext Transport Protocol - Integrated Circuit - International Business Machines - Information and Communication Technology - Integrated Drive Electronics -Input/ Output - Internet Protocol - Interrupt Request - Information Technology - Industry Standard Architecture - Junction Field Effect Transistor
JPEG LAN LED LBA LSB MAN MB MHz MIDI MPEG MODEM MPU NTFS OCR OS PATA PC PCB PCI PIC PPI PDF PNG PnP PS/2 RAID RAM RMW R/W ROM RGB SATA SCSI SDRAM SRAM SVGA SMART
- Joint Photographic Experts Group - Local Area Networking - Light Emitting Diode - Logical Block Addressing - Least Significant Bit - Metropolitan Area Network - Megabyte - Megahertz - Musical Instrument Digital Interface - Motion Pictures Experts Group - Modulator Demodulator - Microprocessor Unit - New Technology File System - Optical Character Recognition - Operating System - Parallel ATA - Personal Computer - Printed Circuit Board - Peripheral Component Interconnect - Programmable Interval Controller - Programmable Peripheral Interface - Portable Document Format - Portable Network Graphics - Plug-and-Play - Personal System/2 - Redundant Array of Independent Disks - Random Access Memory - Read/Modify/Write - Read/Write - Read Only Memory - Red Greed Blue - Serial ATA - Small Computer System Interface - Synchronous Dynamic RAM - Static RAM - Super Video Graphics Array - Self-Monitoring, Analysis, and Reporting Technology
SSRAM TCP/IP URL USB VGA VIRUS WAN WAP Wi-Fi WLAN www
- Synchronous Static RAM - Transmission Control Protocol / Internet Protocol - Uniform Resource Locator - Universal Serial Bus - Video Graphics Array/Adapter - Vital Information Resource Under Seize - Wide Area Network - Wireless Application Protocol - Wireless Fidelity - Wireless Local Area Network - World Wide Web
As A technician, you should know and be able to identify the components found in a typical personal computer system. The PC is modular by design. It is called a system because it includes all the components required to make a functional computer. System unit – The main computer cabinet, usually referred to as a case, housing the primary components of the system. This includes the main logic board (System board or mother board), processor, memory, disk drives, switching power supply, and the interconnecting wires and cables. The system unit also includes expansion cards to provide audio, video, networking and other functionality. Expansion cards vary from system to system.
Keyboard – The most familiar computer input device, the keyboard is used to introduce characters and commands into the system.
Mouse – An input device used with graphical user interfaces (GUI) to point to, select, or activate images on the video monitor. By moving the mouse along a surface, the user can cause a cursor on the display to move in a corresponding manner.
Video display – A Visual output device that displays characters and graphics on screen.
Printers – A hard copy output device that applies data to paper. Normally, methods of placing information on a page include dotmatrix printer, inkjet printer and laser printer.
Speakers – deliver voice,
Audio output devices used to music and coded messages.
System Unit Cases The system unit case is typically a metal chassis and removable cover that includes a plastic front panel for aesthetic purposes. The box typically contains the basic parts of the computer system. PCs have been packaged in various case designs. Each design offers characteristics that adapt the system for different environments. Primary characteristics for case design include the following:
Ventilation characteristics Total drive capacity Portability Mounting methods for the printed Circuit boards Footprint(the amount of desk space the case takes up)
With this list of characteristics. PC case designs fall into four basic styles:
1. Desktops – PC units that are designed to sit horizontally on a standard desktop behind a keyboard and mouse, usually with the display monitor sitting on the top of the case(hence the name). These cases are typically wider than they are tall.
2. Low-profile desktops – A special variety of desktop case, referred to as low-profile desktops that reduce the vertical height of the unit by using a short bus extender card, called a backplane that mounts in an expansion slot and permits option adapter cards to be mounted in the unit horizontally.
3. Towers – Tower cases are designed to sit vertically on the floor beneath a desk to provide more usable workspace on the desktop. Mini towers and mid towers are short towers designed to take up less vertical space. Tower cases also can be placed on a desktop. Internally, their design resembles a vertical desktop unit. They are considerably less expensive than the larger towers because of the smaller amount of materials needed to produce them. Unlike their taller relatives, mini towers do not provide abundant space for internal add-ons or disk drivers.
4. Portables (laptops) – To free users from the desk, an array of portable PCs have been developed these units package the system unit, input units, and output unit into a single, lightweight package that can be carried along with the user. The capabilities of modern portable computers make them the equivalent of desktop or tower units in most respects.
Inside the system unit The system unit is the main portion of the microcomputer system and is the basis of any PC system arrangement. The components inside the system unit can be divided into four distinct subunits: a switching power supply, the disk drivers, the system board, and the option adapter cards. The major components of interest in a PC system are the following:
Power supply – The component in the system that converts the AC Voltage from the commercial power outlet to the DC voltage required by the computer circuitry.
System board – The main component of a personal computer. It contains the major structures that make up a computer system. Disk drives – The system’s mass storage devices that hold data for an extended time, even when power is removed from the system. Disk drives include hard disk drives, CD-ROM/DVD drives, floppy disk drives, and tape drives.
Adapter cards – Interface cards used to enhance the basic system with additional functions. Examples of common adapter cards include video display adapters, modems, and Local Area Network (LAN) cards.
Signal cables – Connecting cables, typically configured in a flat ribbon format, that pass control signals and data between system components such as disk drives and the system board.
Form factor Form factor is a term used to describe specifications for physical dimensions and electrical compatibility that enables components from different manufactures to work together. In a PC, from factor is used to describe system board and adapter card sizes, mounting hole patterns for system boards and power supplies, microprocessor placement, and airflow. These factors determine whether component (Such as a system board) will fit properly with component (Such as a system unit case) and connect to component (Such as a power supply).
You should be aware of the three major active form factors: ATX, BTX, and NLX. 1. The Advanced Technology Extended (ATX) form factor was introduced in the mid 1990s as an upgrade to the IBM PC-AT standard that had become the pseudo standard form factor for PCs. It continues to be most widely used form factor currently in use with PC components. 2. The Balanced Technology Extended (BTX) form factor is a newer scalable form factor specification that provides for a wide range of system sizes and profiles. Its main goal is to establish components
positions that optimize cooling outside the case to support higher component operating speeds. The BTX form factor design is incompatible with the ATX standard, except that you are able to use ATX power supplies with BTX boards and systems. 3. The new low-profile extended (NLX) form factor, which is the replacement form factor specification form Intel for the Older LPX lowprofile specification. The NLX specification is designed to support newer PC technologies, such as larger memory modules, advanced microprocessors, and their cooling systems. The NLX system incorporates a backplane that mounts in a slot on the main board and enables adapter cards to be plugged in horizontally. This is one of the major keys to its low profile.
Information Sheet No. 1.1-3 Structure of operating systems
Systems in the Computer System 1. 2. 3. 4. 5. 6. 7. 8.
Process Management Main Memory Management File Management I/O System Management Secondary Management Networking Protection System Command-Interpreter System
PROCESS MANAGEMENT A process is a program in execution: (A program is passive, a process active.) A process has resources (CPU time, files) and attributes that must be managed. Management of processes includes:
Process Scheduling (priority, time management, . . . ) Creation/termination Block/Unblock (suspension/resumption ) Synchronization
Communication Deadlock handling Debugging
MAIN MEMORY MANAGEMENT
Allocation/de-allocation for processes, files, I/O. Maintenance of several processes at a time Keep track of who's using what memory Movement of process memory to/from secondary storage.
FILE MANAGEMENT A file is a collection of related information defined by its creator. Commonly, files represent programs (both source and object forms) and data. The operating system is responsible for the following activities in connections with file management: • File creation and deletion. • Directory creation and deletion. • Support of primitives for manipulating files and directories. • Mapping files onto secondary storage. • File backup on stable (nonvolatile) storage media. I/O MANAGEMENT
Buffer caching system Generic device driver code Drivers for each device - translate read/write requests into disk position commands.
SECONDARY STORAGE MANAGEMENT
Disks, tapes, optical, ... Free space management ( paging/swapping ) Storage allocation ( what data goes where on disk ) Disk scheduling
NETWORKING
Communication system between distributed processors. Getting information about files/processes/etc. on a remote machine. Can use either a message passing or a shared memory model.
PROTECTION
Of files, memory, CPU, etc. Means controlling of access Depends on the attributes of the file and user
SYSTEM PROGRAMS
Command Interpreters -- Program that accepts control statements (shell, GUI interface, etc.) Compilers/linkers Communications (ftp, telnet, etc.)
Modifying the Operating System program for a particular machine. The goal is to include all the necessary pieces, but not too many extra ones.
Typically a System can support many possible devices, but any one installation has only a few of these possibilities. Plug and play allows for detection of devices and automatic inclusion of the code (drivers) necessary to drive these devices. A sysgen is usually a link of many OS routines/modules in order to produce an executable containing the code to run the drivers.
System Calls A System Call is the main way a user program interacts with the Operating System.
Two ways of passing data between programs.
Shared Memory
These are examples of various system calls.
How An Operating System Is Put Together A SIMPLE STRUCTURE:
Example of MS-DOS.
Application Programming Resident System Programming MS-DOS Drivers ROM - BIOS Device Drivers
A LAYERED STRUCTURE: Example of Windows 2000
System Services Windows Security VM Process MGR Reference Manager Manager & GDI Monitor IO Graphics Manager Device Windows 2000 Kernel Drivers Hardware Abstraction Layer (HAL) Virtual Machine In a Virtual Machine - each process "seems" to execute on its own processor with its own memory, devices, etc. The resources of the physical machine are shared. Virtual devices are sliced out of the physical ones. Virtual disks are subsets of physical ones. Useful for running different OS simultaneously on the same machine.
Protection is excellent, but no sharing possible. Virtual privileged instructions are trapped.
Virtual User Virtual Machine Monitor Mode
Physical User Physical Machine
Example of MS-DOS on top of Windows XP
DOS APPLICATION BIOS DRIVERS Physical Windows XP
User Physical Machine
Information Sheet No. 1.1-4 Familiarization with the various computer systems’ components and peripherals system configuration/ settings of computer systems and devices A peripheral device connects to a computer system to add functionality. Examples are a mouse, keyboard, monitor, printer and scanner. Learn about the different types of peripheral devices and how they allow you to do more with your computer. A computer peripheral is a device that is connected to a computer but is not part of the core computer architecture. The core elements of a computer are the central processing unit, power supply, motherboard and the computer case that contains those three components. Technically speaking, everything else is considered a peripheral device. However, this is a somewhat narrow view, since various other elements are required for a computer to actually function, such as a hard drive and random-access memory (or RAM). Most people use the term peripheral more loosely to refer to a device external to the computer case. You connect the device to the computer to expand the functionality of the system. For example, consider a printer. Once the printer is connected to a computer, you can print out documents. Another way to look at peripheral devices is that they are dependent on the computer system. For example, most printers can't do much on their own, and they only become functional when connected to a computer system. Types of Peripheral Devices There are many different peripheral devices, but they fall into three general categories: Input devices, such as a mouse and a keyboard Output devices, such as a monitor and a printer
Storage devices, such as a hard drive or flash drive Some devices fall into more than one category. Consider a CD-ROM drive; you can use it to read data or music (input), and you can use it to write data to a CD (output). Peripheral devices can be external or internal. For example, a printer is an external device that you connect using a cable, while an optical disc drive is typically located inside the computer case. Internal peripheral devices are also referred to as integrated peripherals. When most people refer to peripherals, they typically mean external ones.
Install Equipment Device System
Information Sheet No. 1.2-1 Basic computer configuration set up
You have a new computer and are ready to set it up. While this may seem like an overwhelming and difficult task, it is actually quite simple. It doesn't matter what brand of computer you have because most computers are set up in a similar way. If you're setting up a newly purchased computer that's still in the box, you'll probably find a how-to guide in the packaging that includes step-by-step details. However, even if it didn't include instructions you can still set up the computer in a few easy steps. In this lesson, we'll go through the different steps needed to set up a typical computer. Setting up a desktop computer
Step 1 Unpack the monitor and computer case from the box. Remove any plastic covering or protective tape. Place the monitor and computer case where you want on a desk or work area.
has good air flow. This will help to prevent overheating.
Think about where you want your desk or work area to be located, and where you want your monitor, computer case, and other hardware to be. Be sure to place your computer case in an area that is well ventilated and that
Step 2 Locate the image cable, you
Step 3
the monitor cable. There are several types of monitor cables, so one on your computer may not look like the one in the at the left. If you're having trouble finding your monitor refer to the instruction manual for your computer. (If have an all-in-one computer that's built into the monitor, you can skip to Step 4).
covered it. Many way. you
Connect one end of the cable to the monitor port on the back of thecomputer case and the other end to the monitor. Hand tighten the plasticscrews on the monitor cable to secure
computer cables will only fit a specific If the cable doesn't fit, don't force it or might damage the connectors. Make sure the plug aligns with the port, then connect it. To figure out which cables belong in which ports, try our Connecting Cables interactive.
Step 4
Unpack the keyboard and determine whether it uses a USB(rectangular) connector or a PS/2 (round) connector. If it uses a USB connector, plug it into any of the USB ports on the back of the computer. If it uses a PS/2 connector, plug it into the purple keyboard port on the back of the computer.
Step 5 Unpack the mouse and determine whether it uses a USB (rectangular) connector or a PS/2 (round) connector. If it uses a USB connector, plug it into any of the USB ports on the back of the computer. If it uses a PS/2 connector, plug it into the green mouse port on the back of the computer. If your keyboard has a USB port, you can connect your mouse to the keyboard instead of connecting it directly to your computer. If you have a wireless mouse or keyboard, you may need to connect a Bluetooth dongle (USB adapter) to your computer. However, many computers have built-in Bluetooth, so a dongle may not be necessary.
Step 6 If you have external speakers or headphones, you can connect them to your computer's audio port (either on the front or the back of the computer case). Many computers have color-coded ports.
Speakers or headphones connect to the green port, and a microphone connects to the pink port. The blue port is the line in, which can be used with other types of devices. Some speakers, headphones, and microphones have USB connectors instead of the usual audio plug. These can be connected to any USB port. In addition, many computers have speakers or microphones built into the monitor. Step 7 Locate the two power supply cables that came with your computer. Plug the first power supply cable into the back of the computer case, and then into a surge protector. Then, using the other cable, connect the monitor to the surge protector. Step 8 Finally, plug the surge protector into a wall outlet. You may also need to turn on the surge protector if it has a power switch. If you don't have a surge protector, you can plug the computer directly into the wall. However, this is not recommended because electrical surges can damage your computer.
Setup complete Your basic computer hardware is now set up. Before you start it up, spend some time arranging your workspace. A workspace that is arranged well can improve your productivity and promote health.
Challenge!
If you have a desktop computer that is already set up at home, take a look at it. o Look at the monitor cable, and see where it connects to the computer case and monitor. o Locate the power cords for the monitor and computer case. o Locate the audio ports. Does your computer have a VGA monitor port, or another kind? Do you have a USB or PS/2 mouse? Do you have a USB or PS/2 keyboard? Is your computer plugged into a surge protector?
Step-by-step how to set the computer, boot sequence to boot from installation media. BIOS ROM (Basic Input Output System) has a built in Setup program that allows users to modify the basic system configuration. The Setup program store the computer information in CMOS RAM that is powered by a little battery that is located on the computer motherboard so that it will retain the computer information even if the computer is turned off. To make computer to start or to boot from the CD-ROM, we need to configure the Bios Setup or CMOS Setup program and set the first boot sequence to CD-ROM drive.
How to enter the BIOS / CMOS Setup Program Utility.
1. When the computer power on, black screen appear on you monitor, wait until the message appears briefly at the bottom of the screen. example of the massage at the bottom of the computer boot up screen: 2. From the boot up screen message above, we know that the key need to press to enter the BIOS setup is [F2] key. Now press [F2] key to enter the setup program. This key may be vary from one machine to other machine, because this is key base on the manufacture of the BIOS Setup program. Note: Other key that commonly used to enter the CMOS setup (BIOS setup) Delete key. Esc key. F1 key. F2 key. F3 and F2 key. F10 key. Ctrl + Alt + Esc key. Ctrl + Alt + S key. How to change the boot sequence. 3. Press [F2] key until you see the BIOS Setup Utility screen, then go to the Boot Option tab then change the Boot sequence to CD-ROM drive as the first boot device. NOTE: Use the < + > key to move the CD-ROM Drive up. Make sure that you read help menu on or blow the window screen
Item Specific Help Key used to view or configure devices: < Enter > expends or collapses devices with a + or < Ctrl + Enter > expands all < Shift + 1 > enables or disables a device. < + > and < - > moves the device up or down. < n > May move removable device between Hard Disk or Removable Disk < d > Remove a device that is not installed. 3. Save the configurations changes and exit the BIOS Setup / CMOS Setup Utility by pressing the [F10] and then hit [ENTER] key to 'Save configuration changes and exit now?'.
Item Specific Help Exit System Setup and save your changes to CMOS. NOTE: Press [ F10 ] key to Save all the CMOS changes and Exit the BIOS / CMOS Setup Utility. Keyword: set computer boot sequence, change boot sequence, boot cd, boot from cdrom, boot sequence, boot from installation media, boot from cd, boot from cd rom, set boot sequence, bios setting, cmos setting, change cmos setting, change bios setting, computer boot sequence, boot installation media, boot CD-Rom.
Three Basics Kind of Computer Analogue Computer • Analog computers are used to process analog data. Analog data is of continuous nature and which is not discrete or separate. • Such type of data includes temperature, pressure, speed weight, voltage, depth etc.
• These quantities are continuous and having an infinite variety of values. Digital Computer • A Digital Computer works with digits to represent numerals, letters or other special symbols. • Digital Computers operate on inputs which are ONOFF type and its output is also in the form of ONOFF signal. • Normally, an ON is represented by a 1 and an OFF is represented by a 0. • A digital computer can be used to process numeric as well as non-numeric data. Hybrid Computer • A hybrid is a combination of digital and analog computers. • It combines the best features of both types of computers, i-e. It has the speed of analog computer and the memory and accuracy of digital computer. • Hybrid computers are used mainly in specialized applications where both kinds of data need to be processed. Therefore, they help the user, to process both continuous and discrete data. Computer Operations A. Input • It is the process of capturing or acquiring the information, or it is the process of accepting data or information, by using input the computer can do any process. • Information or data that is entered into a computer or computer device using an input device. • Data is gathered – Manually – Automatically – Both Types of Computer Input • Data – the raw facts given to the computer. • Programs – the sets of instructions that direct the computer. • Commands – special codes or key words that the user inputs to perform a task. • User response – the user's answer to the computer's question.
B. Processing • • • • •
It is the transformation process to convert the input into output. A process is an instance of running a program. It cause the computer to follow instructions from the Memory. Perform by Central Processing Unit (CPU). The CPU has three parts: – Arithmetic / Logic Unit (ALU) – Control Unit – Input / Output Unit (I/O)
Arithmetic / Logic Unit (ALU) • The part of a computer that performs all arithmetic computations, such as addition and multiplication, and all comparison operations. Control Unit • The control unit is the circuitry that controls the flow of data through the processor, and coordinates the activities of the other units within it. Input / Output Unit (I/O Unit) • The computer components that control input and output devices. C. Computer Output • It is the result, which comes from the transformation process or it is the outcome of the process. • Anything that comes out of a computer. • Example: – Report – Music – Graphic – Video clip Types of Computer Output • Hard copy – Printed on paper or other permanent media. • Soft copy – A soft copy is the unprinted digital document file. – Displayed on screen or by other non-permanent means. – It can be transported from one computer to another. Categories of Output
• Text documents – reports, letters, memo. • Graphics – charts, graphs, pictures • Multimedia – combination of text, graphics, video, audio
D. Storing • It is the process of storing or retaining the data or information or instructions, so that the user can retain and retrieve it whenever required. • Capability to store information after processing. • Storage are used to store programs and data when they are not being used in memory. E. Controlling • It is the process of directing the manner and sequence in which all the operations are to be performed.
Hardware vs. Software • Hardware is any part of your computer that has a physical structure, such as the computer monitor or keyboard. • Software is any set of instructions that tells the hardware what to do. It is what guides the hardware and tells it how to accomplish each task.
Information Sheet No. 1.2-2 System’s Specifications The user has agreed to the project through signing off the user requirement specification. The developers know what to do through the design specification,
A. Software Applications to be used: - These could be off-the-shelf application modified to suit the project or they maybe bespoke applications already available within the company. B. Storage Requirement: - This includes local storage requirements such as hard disk size or it maybe networked storage such as file servers. C. System Memory: -How much memory will be required by the system in order for to run effectively. D. Input Devices needed: -These includes OMR devices, scanners, barcode readers, keyboard, mouse, or touch screens. E. Output Devices to be used: - These may include printers, monitor or even plotter. F. Computing/ Processing Needed: - For a huge system, it may need mainframe level computing power, on the other hand it may only need a standard personal computer to run.
G. Security and Backup Systems: -How the passwords are handled and controlled, authentication methods, how backups are to be handles and so on. H. People Required: -The system may need a fulltime network administrator/ manager and a team of support technicians for example. I. Buildings and offices required: -The system may need a dedicated data room or even an external data centre. J. Network Configuration: -If it is networked system then this includes topology, server, router, hubs to be used. K. System Feeds: - Many systems are inter-linked. For instance an accounting system may be connected to the production system to keep track of products being made and sold.
The main purpose of these specifications dpcumentation is to lay down exactly how the system is made up.
Information Sheet No. 1.2-3 Identifying common symptoms and problems associated with each devices Windows error "Data or no disk loaded" with audio CD Bad or non audio CD is inserted Make sure the CD you have currently in the computer is not bad or being misread by the computer by inserting another known good audio CD into the computer. If another audio CD works it is likely either that the CD is dirty or may be an enhanced CD incompatible with the CD Audio player. Steps on properly cleaning a CD can be found on our cleaning page.
MCI CD audio driver not installed or is corrupt If no audio CD is working in the computer but other CDs work fine, it is likely that the MCI CD audio driver is not installed or is corrupt on the computer. CD-ROM not working in Windows 9x, 2000, or XP. To reinstall or install the MCI CD audio drivers follow the steps below: 1. Click Start, Settings, Control Panel 2. Double-click on Multimedia 3. Click the Advanced tab or Device tab. 4. Double-click Media Control Devices. 5. Double-click CD Audio Device (Media Control). 6. If this device is present and no audio CDs are working, click remove on the general tab in CD Audio Device (Media Control) properties. 7. Close out of all open Windows to get back to the Control panel 8. In Control panel double-click Add New Hardware. 9. Click Next, select No, click Next -- In the box listing the available hardware, select Sound Video and Game controllers and click Next. 10. In the Manufacturers box select Microsoft MCI. 11. In the Models box select CD Audio Device (Media Control). 12. Click Next and Finish. 13. Once Windows has completed the installation of the new device, reboot the computer.
My computer is running slow, what steps can I do to fix it? Tip: This page only covers an overall slow computer and not a computer that has a slow boot up or slow Internet.
Below are steps for Microsoft Windows users that can help speed up the computer or determine why the computer is running slow. Reboot If your computer has not been rebooted recently, make sure to reboot it before following any of the steps below.
Background programs One of the most common reasons for a slow computer are programs running in thebackground. Remove or disable any TSRs and startup programs that automatically start each time the computer boots. Tip: To see what programs are running in the background and how much memory and CPU they are using, open Task Manager. If you are running Windows 7 or higher, run Resmon to get a better understanding of how your computer is being used. If you have an antivirus scanner on the computer, spyware protection program, or another security utility, make sure it is not scanning your computer in the background. If a scan is in progress, it can decrease the overall performance of your computer. If this is the case, allow the scan to complete and the computer's performance should improve afterwards. Delete temp files
As a computer runs programs, accesses web pages, and is being used in general, temporary files are being stored on the hard drive. Deleting these temp files can help improve computer performance. First, we suggest using the Windows Disk Cleanup utility to delete temporary files and other files no longer needed on the computer. Unfortunately, the Disk Cleanup may not delete all of the files in the temp directory. Therefore, we also suggest deleting temporary files manually by opening the Start menu and type %temp% in the Search field (in Windows XP and prior, click the Run option in the Start menu and enter %temp% in the Run field). Press Enter and a Temp folder should open. You can delete all files found in this folder and, if any files are in use and cannot be deleted, they can be skipped.
Free hard drive space Verify that there is at least 200-500MB of free hard drive space. This available space allows the computer to have room for the swap file to increase in size, as well as room for temporary files. Determining available hard drive space. Regaining computer hard drive space. Bad, corrupted or fragmented hard drive Run ScanDisk, chkdsk, or something equivalent to verify there is nothing physically wrong with the computer's hard drive. Run Defrag to help ensure that data is arranged in the best possible order. Use other software tools to test the hard drive for any errors by looking at theSMART of the drive. Scan for malware
Today, spyware and other malware is a big cause of many computer problems, including a slow computer. Even if an antivirus scanner is installed on the computer, we recommend running a malware scan on the computer. Use the free version ofMalwarebytes to scan your computer for malware. Scan for viruses If your computer is infected with one or more viruses, this can cause your computer to run slow. If your computer does not have an antivirus program installed, you can run Trend Micro's free Housecall online utility to scan for viruses on your computer, as well as remove them. It is also recommended that you install an antivirus program for active protection against viruses.
Hardware conflicts Verify that the Device Manager has no conflicts. If any exist, resolve these issues as they could be the cause of your problem. Update Windows Make sure you have all the latest Windows updates installed on the computer. If you are on the Internet when your computer is slow,make sure all browser plugins are up-to-date. You can also try disabling browser plugins to see if one of them is causing the slowness. Update your drivers Make sure you have the latest drivers for your computer hardware, especially the latest video drivers. Having out-of-date drivers can cause an assortment of issues, including slow performance. Reboot computer again If you have done any of the above steps but your computer is still acting slow try rebooting the computer again at this point.
Memory upgrade If you have had your computer for more than two years, you may need more memory. Today, we suggest computers have a minimum of 1GB ofmemory (RAM) for 32-bit system and 2GB for a 64-bit system. By having enough memory for programs to run within memory, your computer will not need to
swap information stored within memory to theswap file. If your computer hard drive light is constantly active, its a good indication that your computer is continuously swapping information between your memory and hard drive because of the lack of space in memory. Determining how much RAM is installed and available. How much memory or RAM should my
computer have? What type of computer memory to use in a memory upgrade?
Hard drive upgrade One of the biggest bottlenecks of a computer is the hard disk drive. For anyone with a slow computer or just looking for something to upgrade in the computer to improve overall system performance, upgrading from a traditional hard drive to a Solid State Drive (SSD) will significantly improve the overall system performance. Run Registry cleaner We normally do not recommend Registry cleaners. However, if you have followed all of the above steps and your computer is still slow, try running a Registry cleaner on the computer. Computer or processor is overheating Make sure your computer and processor is not overheating. Excessive heat can cause a significant decrease in computer performance because most
processors automatically reduce the speed of the processor to help compensate for heat related issues. What temperature should my processor be running at? Dust, dirt, and hair can also constrict proper air flow inside your computer, which can cause a computer to overheat. Make sure your computer case is clean and fans are not obstructed. Steps on cleaning your computer. Erase computer and start over If none of the above solutions resolve your issues, another option is to either reinstall Windows or erase everything and then start over. Erasing everything and starting over can increase performance by getting rid of old software or drivers that may be on the computer and causing the computer to be slow. Installing a fresh copy of Windows, software programs, and the latest drivers help verify there is no software related issues causing your computer to be slow. Hardware issues Finally, if your computer continues to be slower than normal after going over each of the above recommendations (including erasing and starting over), it's possible that your computer is experiencing a more serious hardware related issue, such as a failing component in the computer. This could be a failing or bad hard drive, CPU, RAM,motherboard, or other component. You can run hardware diagnostic tests using the Ultimate Boot CD (UBCD) utility. This utility provides many diagnostic tests that you can run and determine if your computer has a bad piece of hardware. Old computer If your computer is older than five years, the age of the computer could be the cause of the slow performance. Computers advance in technology and capabilities and newer, more advanced software programs come out to run properly on the new computers. Older computers are not able to run the new programs as well, which can cause them to slow down. If your computer is older than five years, we suggest purchasing a new computer or accept that, if
all the above options do not work to speed up your computer, it will just run slower than a newer computer.
Missing or lost sound in Windows Verify software volume control settings First, verify you see a small sound icon or in the Windows notification area, also known as Systray (bottom right-hand corner of the Windows Desktop). If this icon is missing, follow the steps below. If you see this icon,skip to next section.
Windows 8 1. Open the Control Panel 2. Click the "Taskbar" icon. 3. On the "Taskbar" tab, click the "Customize" button next to "Notification area". 4. Scroll down in the list until you see the "Volume" option and speaker icon. On the right side, in the drop-down list, make sure "Show icon and notifications" is selected. If it is not, select this option. If the drop-down list is grayed out, uncheck the box for "Always show all icons and notifications on the taskbar" to allow you to change the dropdown list selection. 5. If you changed the selection in the drop-down list, click OK in that window and the Taskbar Properties window and close out of the Control Panel.
Windows Vista or 7 1. Open the Control Panel 2. Click the "Taskbar and Start Menu" icon. 3. On the "Taskbar" tab, in the "Notification area" section, click the "Customize" button.
4. Scroll down in the list until you see the "Volume" option and speaker icon. On the right side, in the drop-down list, make sure "Show icon and notifications" is selected. If it is not, select this option. If the drop-down list is grayed out, uncheck the box for "Always show all icons and notifications on the taskbar" to allow you to change the dropdown list selection. 5. If you changed the selection in the drop-down list, click OK in that window and the "Taskbar and Start Menu Properties" window and close out of the Control Panel. Windows XP 1. Open the Control Panel 2. Open the "Sounds and Audio Devices" icon. 3. Verify the "Place volume icon in the taskbar" checkbox is checked. If this option is not available or is grayed out, skip to the next section of this document. 4. If you were able to check this box, click OK and close out of this window and the Control Panel. 5. Double-click the sound icon in the Systray and verify that all the sound volumes are mid-way or higher. Conflicts section If conflicts exists with your sound card or other devices installed in your computer, it is likely that either the drivers are not properly installed for that device or the sound card or other devices are conflicting. If you open the properties of the device that is conflicting and view the properties, additional details about the conflict can be found. Additional information about error codes, as well as help with Device Manager, can be found on our Device Manager section. If you are unable to locate additional information about your issue or are unable to resolve the issue, follow the steps below. 1. Under "Sound, video and game controllers", highlight each device and press the delete key to remove the device. 2. Reboot the computer. 3. As the computer is booting, the system will detect the sound card and any of its devices and reinstall those devices. If prompted for a location of drivers, try pointing it to your sound card CD or your Windows CD. If
this does not work or is unable to locate the proper files, you need to get the latest sound drivers from your sound card manufacturer. Other devices section If Other devices are listed, these could be the sound card or another conflicting device. If any other devices are listed, it is recommended you remove those devices, reboot the computer and let Windows re-detect the devices. If this does not work, determine what device is not being detected and resolve that issue first. Missing sound card section. If you are missing the "Sound, video and game controllers" category in Device Manager, it is likely that the sound card drivers are not installed properly, sound card has been disabled, sound card is bad, or no sound card is available in the computer. First, verify no conflicts or other devices are present in the Device Manager. If these are present, it is likely they are the sound card or devices causing the sound card not to be detected. Second, verify that the computer has a sound card and that the sound card is enabled on the computer. If this is an on-board sound card, you can verify that it is enabled in the CMOS setup. If you have no adapters or cannot click the down arrow to select the correct adapter, close out of this window. In the Control Panel, double-click the System icon, click theDevice Manager tab within Device Manager, and ensure there are no yellow ! or red X. If you have either of these on any of your sound devices, remove everything under "Sound, video and game controllers" and reboot the computer. If after rebooting the computer you still have the same conflicts, double-click on the conflicting device and refer to our Device Manager error code section for additional information on the error code you are experiencing. Verify speaker connections Verify the speaker settings and speakers are not at fault by running through computer speaker troubleshooting.
Sound card drivers If you have followed the above recommendations and you are still unable to get the sound card to work, in the Device Manager, remove all sound, video, and game controllers and reboot the computer. This should cause Windows to reinstall all missing drivers and often can correct corrupt drivers. If this does not work after rebooting the computer, download and install the latest sound card drivers from the computer or sound card manufacturer. A listing of manufacturer web pages for sound card drivers can be found on our sound card driver page. Defective hardware Finally, if all of the above recommendations do not resolve your issue, it is likely that either the sound card is not working and defective or that the operating system is corrupted. We recommend you contact the manufacturer of the sound card or computer for a replacement or additional recommendations.
No display or black screen on a computer monitor Note: This page contains some of the more common monitor troubleshooting options and tips. If you are unable to resolve the issue after trying all options on this page, it is recommended that you take your computer and monitor to a computer repair shop for diagnostic testing. Tip: The following monitor troubleshooting steps are not for users who see a readable picture that gets distorted when Windows opens. 1. Monitor is not on Make sure the monitor is on. If you do not see a power LED (blue, green, or orange light) on the front of the monitor, press the power button until it comes on. If no light comes on after several attempts, make sure the connections are properly connected. 2. Computer is asleep
If your computer monitor was on and you stepped away from the computer, then upon returning, it was black, it is likely that the computer is asleep. Try moving your mouse, clicking the mouse buttons, or pressing any key (space bar) on the keyboard to wake it up. 3. Connections not properly connected
A. Check the data cable Make sure that you are connecting the monitor's VGA cable to the back of the computer in the 15-pin connector, as shown to the right, or the older computer 9-pin connection. Note: Newer computers may be using a DVI or HDMIcable for the monitor. Make sure the data cable you are using is firmly connected to the computer. B. Check the power cable If the data cable is plugged in, make sure the monitor is getting power by verifying there is a light (blue, green, or orange) on the front of the monitor. If you see no lights on the monitor, make sure it is connected to a working wall outlet. If the power cord is removable from the back of the monitor, try replacing it with another power cable. If you still cannot power on the monitor after trying another wall outlet and cable, the monitor is bad and should be replaced. C. Check the LED status
If the monitor has a light on the front, but that status light is orange or flashing, make sure the monitor is not in a suspend mode by moving the mouse or pressing a key on the keyboard. If this does not help, turn the computer and monitor off and reconnect the data cable on the back of the computer and, if removable, on the back of the monitor. Turn the computer and monitor back on. If you still encounter the same issue, continue reading through the other possibilities.
4. Monitor settings are not correct Verify the brightness and contrast are turned up or adjust the brightness and contrast. If adjusting the brightness or contrast has no affect on the monitor, continue reading through the other possibilities. 5. No POST Does the computer beep when it is turned on or does it sound like the computer is working? If the computer does not beep or beeps abnormally, the computer is experiencing a hardware issue or is exhibiting a No POST. Run through the POST troubleshooting steps to determine the failure.
6. Hardware Issue If you have followed the above recommendations and still have the same issue, your computer may have either a bad video card or monitor. The best method of determining this is to do one or both of the suggestions below. Disconnect your monitor and connect it to another computer. For example, try connecting it to a friend or family's computer or a computer at a service center. Borrow a computer monitor and connect it to your computer. If your monitor works on another computer, it is safe to assume that the video card or potentially the motherboard in the computer is bad.
Troubleshooting a bad video card. Troubleshooting a bad motherboard. If another monitor works on your computer, it is safe to assume that your monitor is bad and should be replaced. While it may be possible to have the monitor serviced, it is often cheaper and easier to purchase a new monitor.
General printer troubleshooting A. Printer does not have power indicator First, make sure that the printer is on. When a printer is on it should have some light or LED(usually green) indicating it's receiving power. If you do not have any indicator light, make sure the printer is connected to a working power outlet by verifying each end of the power cable. Next, press the printer power button. If after following the previous steps your printer still does not display a power status indicator, it's likely you are encountering a serious printer issue and we
suggest contacting the printer manufacturer for additional instructions on repair or replacement.
B. Cables not connected properly Your printer should have two cables connected to it: the power cable and the data cable. Make sure the power and data cables (parallel cable or USB cable) are connected to both the printer and computer.
C. Printer error (orange or blinking light) After your printer has completed its initial startup, you should see a solid colored light. If the indicator is blinking or orange often this is an indication of a printer error; like a paper jam or an issue with the ink or toner cartridge. As there are not standards for all printers, if you see a blinking light, visit the manufacturer's site for specific error details.
D. No paper or paper jam Without paper, your printer will not be able to print. Make sure you have paper in the paper loaded into the printer paper cartridge or tray. Next, verify that no printer paper is jammed or partially fed into the printer. If you suspect paper is stuck somewhere it shouldn't be.
E. Inkjet printer ink related issues Often when you're encountering an ink related issue you're printer status indicator light (mentioned above) should be flashing. If this is not occurring you may want to skip to the next section. However, if you've recently inserted a new ink cartridge you may want to try the below suggestions. F. Printer self tests Most printers have a way of printing a test page. This page allows you to determine if the printer is physically working or not. This test is usually accomplished by holding down a series of keys. If you are not sure if your printer has this feature or how to perform it refer to your manual or visit your printer manufacturers website.
In addition to testing the printer using the printer self-test Microsoft Windows users can also perform a software self-test to determine if their computer can see the printer and it's able to print. Follow the steps below to perform this test.
Microsoft Windows users 1. Click Start, Settings, and open Control Panel. 2. Double-click the Printers or Printers and Fax icon. 3. Right-click on the Printer you want to test and click Properties. If you do not see your printer listed your printer is not installed. 4. In the Printers Properties window click the Print Test Page button. 5. If the printer can print a test page, your printer is installed and setup properly. However, if you are unable to print in other programs the program you are attempting to print from has issues. Parallel (LPT) printers If the printer you're connecting to the computer is an LPT (parallel port) printer we also suggest verifying the below suggestions if your printer is not working. Parallel port in CMOS 1. Enter the computers CMOS setup. 2. Once in CMOS verify that your parallel port is enabled or installed. 3. Next, verify the printer or parallel port mode. If your parallel port is set to ECP mode, we suggest trying a different mode. Other parallel device If you have a parallel printer with other parallel devices such as a parallel scanner or zip drive, temporarily disconnect these devices to verify they are not causing your issue.
Mouse not being detected or working in Windows There may be several issues which can cause your mouse to not work properly with Microsoft Windows. This document contains the more common solutions that should be followed in order for best results.
Note: If you are having trouble with a touchpad mouse on a laptop, see our laptop touchpad not working page.
A. frozen
Computer
1. Using the Num Lock key Make sure the computer is not frozen by pressing the Num Lock key on the keyboard. When Num Lock is pressed repeatedly, the Num Lock indicator LED on your keyboard should turn on and off. If this indicator does not change, your computer is frozen; meaning all hardware on the computer (including the mouse) will not work. Reboot the computer to resolve this issue. If you don't have an indicator light, proceed to the next part of this section. 2. Keyboard doesn't have Num Lock indicator light If your keyboard does not include the LED described in the previous section, anywhere in Windows, press the Ctrl+Alt+Del keys at the same time. This action should bring up a blue Windows options screen (you may leave this menu by pressing the Esc key). If you are not taken to the blue screen within a few seconds, your computer is frozen. Reboot your machine to resolve this issue. B. Mouse conflict If any new hardware has been recently installed on the computer, remove it to help verify the new hardware is not causing a conflict with your existing mouse.
C. Not connected properly 1. USB mouse If you are using a USB mouse, disconnect the mouse cable and then reconnect to a different USB port. If the mouse is connected to a USB hub, unplug the mouse cable and the connect it to a USB port on the back of the computer. 2. PS/2 mouse If you are using a mouse with a PS/2 connection, check the back of the computer to verify that it is plugged into the PS/2 mouse port and not the PS/2 keyboard. If the mouse has worked properly in the past (I.E. this is not a new mouse), turn off the computer, then disconnect and reconnect the mouse. Note: A PS/2 mouse should not be disconnected and reconnected while a computer is turned on. Tip: If the computer's keyboard is working, you can shutdown Windows properly by pressing the Windows key, and then using the arrow keys to move to the shut down option on the Start Menu. 3. Wireless mouse 1. Make sure the mouse is receiving power by checking for some indication of power (usually a light). If your mouse has a power switch, it is often located on the bottom side. 2. If the mouse does not appear to be on, replace the batteries. 3. Make sure the wireless receiver is within range and is not blocked by another object. 4. Disconnect the wireless USB adapter and try plugging it into a different port.
D. Mouse software or driver conflict Boot into Windows Safe Mode. If the mouse is working in Safe Mode, there is likely adriver or software conflict. To fix this problem, follow the steps below. 1. Open Windows Device Manager.
2. Expand the mouse (mice) option in Device Manager by clicking the + symbol. 3. Remove all mice listed by highlighting each device and then pressing the Delete key on the keyboard. If the mouse still does not work in Normal Windows, follow the basic troubleshooting steps for your version of Windows.
E. Outdated or missing mouse driver Check if a driver has been installed for the mouse. You can check in the Device Manager for this. While Windows may have a standard or default driver for the mouse, installing a driver for your specific mouse may fix the issue. You can check our driver list page to find links to some of the more popular manufacturers' websites to download a driver for the mouse. If a driver is installed for the mouse, it is recommended that you check if there is an updated driver for the mouse. Updating the driver may fix issues with a non-functioning mouse.
F. Hardware issues 1. Bad Port If the previous solutions did not solve the problem, try another mouse. If that mouse works, try the mouse that is not working with another computer. If multiple mice do not work, the likely issue is the port you are connecting the mouse to. If you are using the PS/2 or USB port on the back of the computer, the motherboard is potentially bad and would need to be replaced. 2. Bad Mouse If the mouse does not work with more than one computer, the mouse is bad and should be replaced. If you are using a wired mouse, check the mouse wire. If the wire has been partially cut or is frayed, this is likely the cause of the mouse not working. Replace the mouse if this is the case. G. Corrupt operating system files
If all of the above solutions do not resolve the issue, there is a possibility of corrupt system files in the operating system. You may need to run an operating system repair using the system installation disc. Another option, and possibly less drastic, is to activate a restore point in the operating system prior to when the mouse stopped working. This restore point can restore the corrupt system files to a working state and resolve the issue.
No power or computer does not turn on Notice: If the computer is turning on but is not posting (beeping) or giving any picture on the display. Note: This page relates primarily to desktop computers. For more specific troubleshooting steps for a laptop computer. If you are uncertain if the computer is turning on or not, this can be checked by locating any fans in the computer or visible from the outside of the computer. If these fans are spinning, the computer is receiving power and this document may not apply to your issue.
A. Power cord not connected properly
Verify that the power cord is connected properly to the wall and the back of the computer. If it appears to be connected properly, disconnect and reconnect both ends of the power cord to make sure the cable is not loose. If you have a power strip (surge protector) or switch used to turn everything on at once, temporarily disconnect the computer power cord from that switch and connect it directly to the wall. This helps verify that the strip or switch is not bad. Verify that the outlet works by connecting another electrical device to that switch.
B. Third-party hardware
If additional hardware has been recently added to the computer, it is recommended that you temporarily disconnect or remove the hardware from the computer to verify it is not preventing your computer from turning on. Note: If the computer was working fine before you added the new hardware, removing the third-party hardware did not resolve the issue, and the computer is not beeping but is turning on. Verify that the cable supplying power to your computer is not bad or damaged by using another power cable. If you have a standard CRT monitor, this cable can be used in place of the computer power cable. If you have a portable computer or laptop, when the cables are plugged into the laptop, you should see a power light or battery charge light. If this light is seen, this is a good indication that the power cable is good.
C. Incorrect power supply If you are building your own computer or if the computer has never turned on since you purchased it, you may have a defective power supply that does not supply enough power or the incorrect power supply for your computer. Verify your power supply meets the requirements of your motherboard and processor. How do I determine how big my power supply is? How big of a computer power supply should I get?
D. Bad battery If your computer is a laptop or portable computer that utilizes a battery for mobility, it may be causing your issue. If your computer powers on when the cable is connected to the portable computer, but not when it is disconnected, we recommend you purchase a new battery. If your computer does not power on when the battery is connected and when the power cable or charger cable is connected, try removing the battery and seeing if the computer can power on with only the power cable connected. If no power is still received, skip to the final section.
E. Bad power supply, power button, power board, or inverter If, after following the above sections, your computer still receives no power, it is likely that a hardware component in the computer has failed. It is high possibility that the power supply has failed. If you do not plan on replacing the power supply yourself or if you have a portable computer, we recommend having the computer serviced by your computer manufacturer or a local computer repair shop. If you have a desktop computer and plan on trying to repair the computer yourself, we recommend you replace the components in your computer in the below order. 1. First open the computer and verify the power connections. We recommend disconnecting the main power cable and reconnecting the power cable to make sure it has not become loose. Also, verify the power button cable is correctly connected to the motherboard. 2. Replace the power supply with a new power supply. 3. Replace the motherboard.
Basic network troubleshooting Because of the variety of network configurations, operating systems, setup, etc. not all of the below information may apply to your network or operating system.
Note: We cannot assist you with network problems due to an unknown passwords or unknown ISP settings. Since we have no method of verifying or determining this information.
Adapter resources
Verify that the network adapter is properly installed and detected by the computer with no conflicts. If you're using Microsoft Windows check in Device Manager and verify there are no errors and "Network adapters" is present with each network adapter installed in the computer listed, similar to the example on the right.
How do I get into Windows Device Manager? Identifying problems in Windows Device Manager.
If conflicts exist or the network adapter is being detected as an Other device. The network card has not been properly installed in the computer. Try letting Windows re-detect and install the Network card by removing the network adapter and any other conflict devices from Device Manager and then rebooting the computer. If Windows re-detects the card but does not find the drivers, download the network adapter drivers from the computer manufacturer or the network card manufacturer.
How do I remove a device in Windows Device Manager? Listing of network drivers and network card manufacturers.
Verify connections Wired Network
If this is a wired network, verify that the network cable is properly connected and make sure the LEDs next to the network jack are properly illuminated. For example, a network card with a solid green LED or light usually indicates that the card is either connected or receiving a signal. If the green light is flashing, this is an indication of data being sent or received. In the picture is an example of LAN port with two LED indicators next to the RJ-45 port. With this port, one LED will light up if connected properly and the other will flash when transmitting data. If there are no lights or the lights are orange or red the card may be bad, not connected properly, or that the card is not receiving a signal from the network. If you are on a small or local network and have the capability of checking a hub, switch, or router verify that the cables are properly connected and that it has power. If after checking the connections the LED indicators appear bad, the network adapter, port, or cable may be defective. Wireless Network If you're using a laptop with a wireless network make sure if the laptop has a Wi-Fi button that it is turned on. Many laptops have a Wi-Fi button that allows the wireless network to be turned on and off. In the picture is an example of a Wi-Fi button that is currently enabled.
If the Wi-Fi button is turned on, make sure you're connecting to the correct WiFi hotspot by right-clicking on the Network icon in the Windows notification area and clicking "Connect to a network". Usually, the network with the strongest connection (the most bars) will be your wireless router. Finally, when connecting to most wireless networks you need to enter the proper SSID (password) in order to connect to the network. If the incorrect SSID has been entered you cannot access the network.
Adapter functionality Verify that the network card is capable of pinging itself by using the ping command. Windows users can ping the computer from a Windows command line. Unix and Linux users can ping from the shell. To ping the card or the localhost, type either ping 127.0.0.1
or ping localhost
Doing either of the above commands should get replies from the network card. If you receive an error or if the transmission fails the network card is not physically installed into the computer correctly, has the incorrect drivers, or that the card is bad.
Connect to the router If all of the above steps have been checked and your network has a router, make sure the computer can connect to the router by performing the below commands. Determine the routers address Using the ipconfig command (or ifconfig command for Linux) determine the router's address by looking at the Gateway address. Below are the steps for Microsoft Windows users, Linux users can substitute ipconfig for ifconfig.
1. Open the Windows command line. 2. From the command prompt type ipconfig and press enter. This command should give you an output similar to the example below. Ethernet adapter Local Area Connection: Connection-specific DNS Suffix . : computerhope.com. IP Address. . . . . . . . . . . . : 192.168.1.103 Subnet Mask . . . . . . . . . . . : 255.255.255.0 Default Gateway . . . . . . . . . : 192.168.1.1 The Default Gateway is the address of your router. Most home routers have a gateway address that starts with 192.168 like the address shown above. Assuming your gateway address is 192.168.1.1 attempt to ping the router to see if it can send and receive information by running the below command.
ping 192.168.1.1
If you get replies back from the router, the connection between your router and computer are good, and you can skip to the next step. If you do not receive any replies back from the router either the router is not setup properly or your connection between the router and the computer are not correct. Reset your router to make sure it is not a problem with your router by following the steps below.
1. Turn off the power to the computer and leave it off. 2. Unplug the power to your router and cable modem or DSL modem. 3. Leave the power cables disconnected for 10-15 seconds and then plug in your modem and then your router again. 4. Finally, turn on your computer again and repeat this step to see if you can ping your router. If you're using a wireless network and have followed all the above steps and still are unable to ping the router try turning off the computer again and connect the computer to the router using a cable instead of trying to connect using wireless. If a wire does also not work connect the manufacturer of the router for additional support or replacement. Firewall If your computer network utilizes a firewall, make sure all required ports required are open, especially port 80, which is the HTTP port. If possible, disable the firewall software program or disconnect the computer from the firewall to make sure it is not causing the network problems.
Internet is not working If you're able to ping the router, but are still unable to connect to the Internet, either your router is improperly configured or the ISP is having issues. Note: Some ISPs such as Comcast require special software be installed. Make sure any software included with your Modem or other hardware has been installed on at least one computer if you are setting up a new Internet connection. If your Internet has been working but recently stopped working, give it a few minutes to make sure it is not a temporary outage. If after waiting a few minutes, you still have problems and you have not disconnected the power to your router and modem already follow the steps below. 1. Turn off the power to the computer and leave it off. 2. Unplug the power to your router and cable modem or DSL modem. 3. Leave the power cables disconnected for 10-15 seconds and then plug in your modem and then your router again. 4. Finally, turn on your computer again and repeat this step to see if you can ping your router. If after following the above steps the Internet is still not working, open the Windows command line and run the below command.
ping google.com
Running the above command should get a reply from Google. If you get a reply, this is an indication that the Internet is working, but you may be encountering a problem with the Internet browser you are using to browse the Internet. Try an alternative browser such as Firefox or Chrome.
If you're getting no reply from Google, your router or modem is not reaching the Internet. If you have a router, make sure your router has DHCP enabled and that theWAN or Gateway address is the proper ISP address. Finally, after verifying all of the above settings if your Internet is still not working we suggest contacting the ISP to make sure it is not a problem on their end and to assist you further with any special configurations that may not be mentioned in this document.
Additional troubleshooting Another method of determining network issues is to use the tracert command if you are a Windows user or the traceroute command if you are a Linux or Unix variant user. This command gives you an overview of each of the devices (routers) a packet travels (hops) over a network and can give you an idea of where a problem exists in your network or outside of your network. To use this command you must be at the command line and type one of the below commands depending on your operating system. tracert google.com
or traceroute google.com
If run successfully you should begin to see each hop between the computer and network devices. When the connection fails, determine what device is causing the issue by reviewing the traceroute listing.
Information Sheet No. 1.2-4 Troubleshooting and isolating PC hardware problems
5 Common Computer Problems & Solutions
Blue Screen of Death (BSoD) Many people think of blue as a calming color; however, when it comes up on your computer screen with a bunch of white text, it probably has the opposite effect. The blue screen of death (BSoD or STOP Error) may appear to be one of the scariest computer problems you'll come across. However, all your computer may need is for you to reboot it. This STOP error appears on your screen for a variety of reasons: failing hardware, damaged software, corrupt DLL files, problems with drivers and more. The remedy for a blue screen of death depends on the original problem. The screen provides you with codes that can help you identify and fix your computer problems. Missing DLL File Dynamic-Link Library (DLL) files house information for your operating system on how to perform certain functions. Occasionally, your computer loses DLL files or something damages them. When your PC can't read the particular DLL file, it doesn't know how to respond in certain situations. You may have a missing or corrupt DLL file if you receive an error message every time you perform a certain function, such as saving. If your computer problems are stemming from missing and damaged DLL files, you can restore them by downloading them back onto your PC. Applications That Won't Install If you're having trouble with an application not installing, it may be because your computer doesn't have enough hard drive space. If this is the case, you need to free up some space. This is one of the computer problems that's, well, least problematic. You can free up some hard drive space by getting rid of files and folders you don't need. These may be temporary files, duplicate files or data for software you've uninstalled. Applications Run Slowly There are several reasons software might be running at turtle speed. You may have computer problems that involve your operating system or an application, your operating system might be missing updates or your computer doesn't have enough hard drive space. If you don't have enough hard drive space, you can scan, clean and optimize your hard drive. Abnormal Applications Behavior Computer problems that involve applications acting strangely oftentimes leave you wondering what has happened. Your application has been
working just fine, but now, seemingly without reason, it is doing something strange. For instance, your Word document will no longer show the top margin of your document. It still says it's there, and when you print it, there's not a problem. You just can't see it on your monitor. If this is happening, you may want to restart your computer. Conducting an internet search for the type of problem you're experiencing or consulting your user manual may help you as well. Using System Repair Software If you have computer problems, chances are, system repair software can help you fix it. Most of these applications can repair operating system problems that lead to the Blue Screen of Death. They can also replace missing or damaged DLL files. System repair software can also free up space you need for another application, and it can optimize your computer so it runs faster. It may even identify problems you're having with applications, but it depends on the software you use and the application that's having problems.
Information Sheet No. 1.2-5 Diagnosing and troubleshooting hardware conflicts
How to Diagnose a Computer Problem?
Step 1: Check the POST.
POST stands for Power On Self Test. This is generally the first or second thing that appears on a computer after turning on the power. This appears before the operating system begins to load. The POST will display any problems found with hardware that makes the computer unable to boot, POST may also display problems with hardware that allow the computer to boot, but not operate at its full capacity during operation.
Step 2: Notice the load time of the OS (operating system). A longer than usual load time may indicate seek errors (or other errors) in the hard drive.
Step 3: Notice any graphics problems once the OS has loaded. Reduced graphics may indicate driver failures or hardware failures with graphic cards.
Step 4: Perform an auditory test. An auditory test is an unorthodox, but still effective way of judging how hard a computer is working. With the computer on and running, play any decent length audio file (usually above 30 secs). If the audio is choppy or slow, it usually means that the processor is working at an elevated level, or there is not enough RAM to run all programs loading. Changing the startup sound is a great way to apply this test. Another issue associated with choppy sounds is PIO (Programmed Input/Output) Mode. This affects how the hard drive reads and writes data from a drive. Switching to DMA allows for faster reads and writes, and can sometimes repair choppy audio.
Step 5: Check any newly installed hardware. Many operating systems, especially Windows, can conflict with new drivers. The driver may be badly written, or it may conflict with another process. Windows will usually notify you about devices that are causing a problem, or have a problem. To check this use the Device Manager, this can be accessed by entering the Control Panel, clicking the System icon, clicking theHardware tab, and clicking on Device Manager. Use this to check and arrange the properties of hardware.
Step 6: Check any newly installed software. Software may require more resources than the system can provide. Chances are that if a problem begins after software starts, the software is causing it. If the problem appears directly upon startup, it may be caused by software that starts automatically on boot.
Step 7: Check RAM and CPU consumption. A common problem is a choppy or sluggish system. If a system is choppy it is good practice to see if a program is consuming more resources than the computer can provide. An easy way to check this is to use the Task Manager, right click on the taskbar select Task Manager, and click the Processestab. The CPU column contains a number that indicates the percentage of CPU the process is consuming. The Memory Usage column indicates how much memory a process is consuming.
Step 8: Listen to the computer, if the hard drive is scratching or making loud noises, shut off the computer and have a professional diagnose the hard drive. Listen to the CPU fan, this comes on a high speed when the CPU is working hard, and can tell you when the computer is working beyond its capacity.
Step 9: Run a virus and malware scan. Performance problems can be caused by malware on the computer. Running a virus scan can unearth any problems. Use a commonly updated virus scanner (such as Norton Antivirus or Avast! Antivirus) and a commonly updated malware scanner (such as Spybot Search & Destroy).
Step 10: Check for the problem in safe mode. As a last ditch effort, check the problem in safe mode. To enter safe mode, tap F8 repeatedly during POST (this works on most systems). If the problem persists in safe mode, it is a fair bet that the operating system itself is to blame.
Information Sheet No. 1.2-6 Installing Computer peripherals, network devices and other I/O
How to Connect the Keyboard, Mouse, Monitor, Speakers, Scanner and Printer in Your Computer? The remaining components for your new computer are called peripherals. These are all external devices that will not be installed inside the case. They will allow you to interact with the computer by inputting commands, viewing the screen as well as printing out documents and pictures. Keep your computer case open and on its side on your table. We are going to attach the peripherals, then start up the computer to make sure everything is working before closing up the case and moving the computer to your workstation.
1. Let's install the keyboard first. All you have to do is remove it from the box and insert the cable into the purple PS/2 socket at the top left of the I/O panel. The I/O panel is the portion of the motherboard that is exposed out the back of the case. Some keyboards have USB connectors that would obviously plug into one of the USB ports on the I/O panel rather than the PS/2 port. 2. To connect the mouse you plug the cable into the green PS/2 socket at the upper right of the I/O panel. Pretty easy stuff here. Some mouse have USB connectors that would obviously plug into one of the USB ports on the I/O panel rather than the PS/2 port. 3. The speakers will also be connected via the I/O panel. If your set of speakers has just one cable it will plug into the pale green Line-Out jack. If you have a fancier set of speakers you may need to use the side speaker jacks as well.
4. The microphone that came in the motherboard box can be plugged into the pink jack that matches it's pink plug. 5. If you will be using a wireless home network be sure to connect the WiFi antenna into the Wi-Fi Antenna In jack at the bottom of the I/O panel. The antenna came in the motherboard box. Most motherboards do not come with a wireless antenna, which means you would have to buy and install a separate wireless network card in your computer. That is another great reason I recommend the Asus M2N32 motherboard. Most scanners and printers are connected via a USB cable to a USB jack on the I/O panel. 6. Connect the printer through a USB port or through a parallel port. 7. Attach the monitor. If you are using an old, bulky CRT monitor you will attach the monitor cable to the analog jack on the externally exposed panel of the video card. If you are using a flat-panel LCD monitor you should use the provided DVI cable to plug in to the DVI jack on the video card. Some monitors come with a DVI adapter to add to the end of the monitor cable in order to plug into the DVI jack. You can attach a flat-panel monitor to the analog jack, but the picture quality won't be nearly as good so don't do that. You have now installed all the components. You computer is essentially fully assembled. You are not done yet however. There are still plenty of things to do before your computer is ready for use.
The next thing we need to do is take the computer for a short spin to make sure everything works properly.
DIAGNOSING AND TROUBLESHO OTING COMPUTER SYSTEM
Plan and prepare for diagnosis of faults of computer systems
Information Sheet No. 2.1-1 Different types of computer systems error
Information Sheet No. 2.1-2 Software as tools for diagnosing computer systems Techniques for Diagnosing Computer System Techniques for diagnosing computer system 1. Computer Diagnosis 2. Rules In Diagnosing Computer System 3. Factors Causing Computer Failures and Defects 4. Problem Isolation 5. Component Isolation Computer Diagnosis Sometimes when the problem with a system is not totally apparent and the problem may be intermittent, using a basic common diagnostic procedure may help determine what is wrong. This procedure has a number of steps that, if followed each time, can be of help. Rules in Diagnosing Computer System 1. Know the facts • Educate oneself on all aspects and operation of computer parts. • Continuous learning on computer technology. 2. Use your common sense
3. Focus on Field Replaceable Units • Identify the different types of FRU that can be used for replacement or subassembly. 4. Proper assembly and disassembly Factors Causing Computer Failures and Defects 1. 2. 3. 4. 5. 6.
Peopleware Firmware Software Hardware Static(ESD) Electricity
Peopleware • Untrained personnel would probably damage programs in PC. Firmware • Programs or software burnt in chips may be corrupted.
Software • Corrupted operating systems would cause the system to fail. Hardware • Defective hardware components would lead to computer malfunction. • Hardware conflicts and viruses can hinder your computers performance. ESD (Electro Static Discharge) • Electro static discharge can easily damage sensitive components in your computer. Electricity • Incoming supply from AC outlet must be regulated, power surges can damage computer units. Problem Isolation
Problem isolation is a detective work in which you need to determine what is out of the ordinary by making detailed observation of what is not working normally and record any information as you proceed. The information you will be able to gather will help diagnose your computer. You need to observe wisely. Look for any abnormalities in the unit, any change in smell or foreign smell, listen to all the sounds, and error codes.
Component Isolation This section will aid in determining components in your system which are failing. First, most systems have 3 major components; monitor, system unit, and printers. Some have multiple external devices. To troubleshoot, you need to isolate major components which are failing to operate.
Information Sheet No. 2.1-3 Hand tools and its uses
Computer Hand Tools When performing computer upgrades, maintenance or troubleshooting, you will often need to remove or replace hardware. You should have a number of key tools in your possession to make this process easy and safe. Though your first thought might be to buy a prepackaged computer toolkit, these types of kits are often cheap or flimsy. Instead, you'll find it worth the cost to assemble your own computer tool-kit, composed of quality, branded tools. Electro-Static Discharge (ESD) Tools Static electricity is easily generated by friction on carpets, tile flooring, clothing, hair, fabric, and etc. The friction of moving air alone will charge suspended parties and cause the buildup of static electrical charges on people and objects in the environment. Grounded antistatic work mats used electrostatic electricity. Examples of ESD Tools:
Anti-static wrist strap
Anti-static wrist strap-used to prevent ESD damage to computer equipment.
Anti-static mat
Anti-static - used to stand on or place hardware on to prevent static electricity from building up.
Hand Tools A hand tool is a device for performing work on a material or a physical system using only hands. The hands tools can be manually used employing force, or electrically powered, using electrical current. Examples of Hand Tools:
Flat head screwdriver
Flat head screwdriver - used to loosen or tighten slotted screws.
Philips head screwdriver
Philips head screwdriver - used to loosen or tighten cross-head screws. Torx screwdriver
Torx screwdriver - used to loosen or tighten screws that have a star-like depression on the top, a feature that is mainly found laptop. Hex driver
Hex driver - sometimes called a nut driver, is used to tighten nuts in the same way that a screwdriver tightens screws. Needle-nose plier
Needle-nose plier - used to hold small parts.
Wire cutter
Wire cutter - used to strip and cut wires. Tweezers
Tweezers - used to manipulate small parts.
Part retriever
Part retriever - used to retrieve parts from location that are too small for your hand to fit. Flashlight
Flashlight - used to light up areas that you cannot see well. Cleaning Tools Having the appropriate cleaning tools is essential when maintaining or repairing computers. Using these tools ensures the computer components are not damage during cleaning. Examples.
Lint-free cloth
Lint-free cloth - used to clean different computer components without scratching or leaving debris. Compressed air
Compressed air - used to blow away dust and debris from different computer parts without touching the components.
Cable ties
Cable ties - used to bundle cables neatly inside and outside of a computer. Parts organizer
Parts organized - used to hold screw, jumpers, fasteners and other small parts and prevents them from getting mixed together. Diagnostic Tools Computers are easier to use and more dependable with each new generation of hardware and operating system update, but that doesn't mean they're problem-free. Here's the most popularb tools for diagnosing your computer problems:
Multimeter
Multimeter -used to test the integrity of circuits and the quality of electricity in computer components.
Loopback Adapter
Loopback Adapter - used to test the functionality of computer ports.
PC Tools for Software and Hardware Trouble Shooting. These are the PC Tools and Components that will be used in PC Hardware and Software Trouble Shootings. A lens A lens is an optical device which transmits and refracts light, converging or diverging the beam. A simple lens consists of a single optical element. A compound lens is an array of simple lenses (elements) with a common axis; the use of multiple elements allows more optical aberrations to be corrected than is possible with a single element. Lenses are typically made of glass or transparent plastic. Elements which refract electromagnetic radiation outside the visual spectrum are also called lenses: for instance, a microwave lens can be made from paraffin wax.
A multimeter A multimeter or a multitester, also
known as a VOM (Volt-Ohm meter), is an electronic measuring instrument that combines several measurement functions in one unit. A typical multimeter may include features such as the ability to measure voltage, current and resistance. ] Multimeters may use analog or digital circuits--analog multimeters (AMM) and digital multimeters (often abbreviatedDMM or DVOM.) Analog instruments are usually based on a microammeter whose pointer moves over a scale calibrated for all the different measurements that can be made; digital instruments usually display digits, but may display a bar of a length proportional to the quantity being measured. A multimeter can be a hand-held device useful for basic fault finding and field service work or a bench instrument which can measure to a very high degree of accuracy. They can be used to troubleshoot electrical problems in a wide array of industrial and household devices such as electronic equipment, motor controls, domestic appliances, power supplies, and wiring systems. An eraser
synthetic soy-based gum.
An eraser or rubber (elsewhere) is an article of stationery that is used for removing pencil markings. Erasers have a rubbery consistency and are often pink or white. Some pencils have an eraser on one end. Typical erasers are made from synthetic rubber, but more expensive or specialized erasers are vinyl, plastic, or gum-like materials. Cheaper erasers can be made out of
An eraser can be used of cleaning the RAM, a memory chip of the PC. Paint brush
brush 1 (brsh) n. 1. a. A device consisting of bristles fastened into a handle, used in scrubbing, polishing, or painting. b. The act of using this device. 2. A light touch in passing; a graze. 3. An instance of contact with something undesirable or dangerous: a brush with the law; a brush with death. 4. A bushy tail: the brush of a fox. 5. A sliding connection completing a circuit between a fixed and a moving conductor. 6. A snub; a brush off.
A vacuum
A vacuum is a space devoid of air or matter, or a tool that uses suction to clean.(noun) 1.
An example of a vacuum is a space with nothing in it.
2.
An example of a vacuum is something used to clean up dirt on a floor.
To vacuum is to clean using a tool that sucks dirt or other elements into a storage container. (verb) An example of vacuum is to clean the dirt off the carpet using a vacuum cleaner.
A soldering gun
A soldering gun is an approximately pistol-shaped tool for soldering metals using tin-based solder to achieve a strong mechanical bond with good electrical contact. The tool has a trigger-style switch so it can be easily operated with one hand. The body of the tool contains a transformer with a primary winding connected to mains electricity when the trigger is pressed, and an incomplete single-turn secondary winding of thick copper with very low resistance. A soldering tip, made of a loop of thinner copper wire, is secured to the end of the transformer secondary by screws, completing the secondary winding. When the primary of the transformer is energized, several hundred amperes of current flow through the secondary and very rapidly heat the copper tip. Since the tip has a much higher resistance than the rest of the tubular copper winding, the tip, used for soldering, gets very hot while the remainder of the secondary warms much less. A tap on the primary winding is often used to light a pilot lamp which also provides illumination of the work piece. Pliers Pliers are a hand tool used to hold objects firmly, for bending, or physical compression. Generally, pliers consist of a pair of metal first-class levers joined at a fulcrum positioned closer to one end of the levers, creating short jaws on one side of the fulcrum, and longer handles on the other side. This arrangement creates a mechanical advantage, allowing the force of the hand's grip to be amplified and focused on an object with precision. The jaws can also be used to manipulate objects too small or unwieldy to be manipulated with the fingers. Diagonal pliers
Diagonal pliers (or wire cutters or diagonal cutting pliers) are pliers intended for the cutting of wire (they are generally not used to grab or turn anything). The plane defined by the cutting edges of the jaws intersects the joint rivet at an angle or "on a diagonal", hence the name. Instead of using a shearing action as with scissors, they cut by indenting and wedging the wire apart. The jaw edges are ground to a symmetrical "V" shape; thus the two jaws can be visualized to form the letter "X", as seen end-on when fully occluded. The pliers are made of tempered steel with inductive heating and quenching often used to selectively harden the jaws.
A Phillips screw driver
A Phillips screw driver is primarily used to fasten and unfasten screws with a star-like hole in their heads. A screwdriver
A screwdriver is a tool for driving screws or bolts with special slots, and sometimes for rotating other machine elements with the mating drive system. The screwdriver is made up of a head or tip, which engages with a screw, a mechanism to apply torque by rotating the tip, and some way to position and support the screwdriver. A typical hand screwdriver comprises an approximately cylindrical handle of a size and shape to be held by a human hand, and an axial shaft fixed to the handle, the tip of which is shaped to fit a particular type of screw. The handle and shaft allow the screwdriver to be positioned and supported and, when rotated, to apply torque. Screwdrivers are made in a variety of shapes, and the tip can be rotated manually or by an electric motor or other motor. The flat head is also one of the most abused tools, often substituted for any number of other tools that might not be available. The fact is the flat head screwdriver is quite useful for more than tightening screws. Used for light prying, scraping, nudging or holding it can be pretty versatile. Treat it too badly, though, and it'll snap, leaving you with a fishing weight in your toolbox. Goggles or safety glasses
Goggles or safety glasses are forms of protective eyewear that usually enclose or protect the area surrounding the eye in order to prevent particulates, water or chemicals from striking the eyes. They are used in chemistry laboratories and in woodworking. They are often used in snow sports as well, and in swimming. Goggles are often worn when using power tools such as drills or chainsaws to prevent flying particles from damaging the eyes. Many types of goggles are available as prescription goggles for those with vision problems. A glove A glove (Middle English from Old English glof) is a garment covering the whole hand. Gloves have separate sheaths or openings for each finger and the thumb; if there is an opening but no covering sheath for each finger they are called "fingerless gloves". Fingerless gloves with one large opening rather than individual openings for each finger are sometimes called gauntlets. Gloves which cover the entire hand or fist but do not have separate finger openings or sheaths are called mittens. Mittens are warmer than gloves made of the same material because fingers maintain their warmth better when they are in contact with each other. Reduced surface area reduces heat loss.
LAN tester
A LAN tester is a circuit used to check the LAN cables. An antistatic wrist strap
An antistatic wrist strap, ESD wrist strap, or ground bracelet is an antistatic device used to safely ground a person working on very sensitive electronic equipme nt, to prevent the buildup of static electricity on their body, which can result in electrostatic discharge (ESD). It is used in the electronics industry by workers working on electronic devices which can be damaged by ESD, and also sometimes by people working around explosives, to prevent electric sparks which could set off an explosion. It consists of a stretchy band of fabric with fine conductive fibers woven into it, attached to a wire with a clip on the end to connect it to a ground conductor. The fibers are usually made of carbon or carbon-filled rubber, and the strap is bound with a stainless steel clasp or plate. They are usually used in conjunction with an antistatic mat on the workbench, or a special static-dissipating plastic laminate on the workbench surface.
A crimping tool A crimping tool is a tool designed to crimp or connect a connector to the end of a cable. For example, network cables and phone cables are created using a crimping tool to connect the RJ-45 and RJ-11 connectors to the end of the cable. In the picture to the right, is an example of what a crimping tool looks like. This example shows a tool capable of crimping both RJ-11 and RJ-45 connectors.
Sharp Pointed Tweezers The Tweezerman Pointed Tweezers feature perfectly aligned, hand filed tips made from 100 stainless steel. The fine, precision design makes eliminating even the most stubborn stray hairs a cinch. Caution: Tweezers are very sharp. Use with care. Keep out of the reach of children. Tweeze in the direction of hair growth, after a hot shower, or use a hot wash cloth to open pores. For ingrown hairs, cleanse skin and disinfect the tips of the tweezers with alcohol. After any work under the skin, clean area with hydrogen peroxide. Always replace protective cap on tweezer tips.
A soldering iron
A soldering iron is a hand tool used in soldering. It supplies heat to melt the solder so that it can flow into the joint between two workpieces. A soldering iron is composed of a heated metal tip and an insulated handle. Heating is often achieved electrically, by passing an electric current (supplied through an electrical cord or battery cables) through a resistive heating element. Portable irons can be heated by combustion of gas stored in a small tank, often using a catalytic heater rather than a flame. Simple irons less commonly used than in the past were simply a large copper bit on a handle, heated in a flame.
Information Sheet No. 2.1-4 Procedures in Diagnosing Computer Systems
Information Sheet No. 2.1-5 Safety precautions
Safety precautions Proper preparation is the key to a successful built. Before you begin, make sure that you have the tool you will need, and secure a clear well-lit workplace. Gather all the components you’ll be using and unpack them at the same time. Find a dry, well-ventilated place to do your work, you should choose an area without carpets, because it tends to create static electricity. Always keep in mind that personal protection is one of the traits of a good technician. Preventive Maintenance Maintenance is keeping something in working order. It includes repair, testing, adjusting, and replacing parts of a computer or a peripheral. Types of Preventive Maintenance • Active • Passive Active – this is carried out before problems develop in a computer unit. Passive – this is carried after problems have developed in the computer unit.
Accident reports Forms used to give specific details with regards to the accidents happed in the laboratory during experiments. Accident reports contain the following details: Name of the person injured Date and time of the accident Type of injury First aid given Action taken to prevent further accidents
General Safety Tips and Reminders
Observe good housekeeping in the area of the machines during and after maintenance. Place removed covers and other parts in a safe place, away from all personnel, while you are servicing the machine.
Dress for the Job Keep your tool case away from walk areas so that other people will not trip over it. Do not wear loose clothing that can be trapped in the moving parts of a machine. Ensure that your sleeves are fastened or rolled up above your elbows. If your hair is long, use hair net or hair cap. Insert the ends of your necktie or scarf inside clothing or fasten it with a nonconductive clip, approximately 3 inches from the end. Do not wear jewelry, chains, metal-frame eyeglasses, or metal fasteners for your clothing.
Electrical safety
Electric current from power, telephone, and communication cables can be hazardous. To avoid personal injury or equipment damage, disconnect the attached power cords, telecommunications systems, networks and modems before you open the server/workstation covers, unless instructed otherwise in the installation and configuration procedure. Precautions Disconnect all power before: Performing a mechanical inspection Working near power supplies Removing or installing main units Before starting work on the machine, unplug the power cord. Never assume that power has been disconnected from a circuit. First, check that it has been powered-off. Always look carefully for possible hazards in your work Moist floors Non-grounded power extension cables Power surges. If an electrical accident occurs: Use caution Switch off power Send another person to get medical aid
Safety Inspection Guide 1. These steps will help you to identify potentially unsafe conditions on these products: Check exterior covers for damage (loose, broken, or sharp edges) Power-off computer. Disconnect the power cord. The power cord should be the appropriate type. Insulation on the power cord must not be frayed or worn out. Remove the cover. Check for any obvious alteration. Use good judgment as to the safety of any alterations. Check for worn out, frayed or pinched cables. Check that the power-supply cover fasteners (screws or rivets) have not been removed or tampered with.
