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Pc maintenance


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The objective of this presentation is to enable primary users to maintain software and hardware parts of a computer. Further guides can be found from my face book page or through my email address or by following on twitter @fita2004.

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Pc maintenance

  1. 1. CHAPTER 1Introduction to Computer System By FITA AYALEW
  2. 2. Objectives Learn that a computer requires both hardware and software to work Learn about the many different hardware Investigate components inside of and connected to a computer Study how to:-  Install new hardware and software  Diagnose hardware and software problems  Solve hardware and software problems  Evaluate new hardware and operating systems By FITA AYALEW
  3. 3. INTRODUCTIONHardware Needs Software to Work• Hardware: physical portion of a computer– Components: monitor, keyboard, memory, hard drive• Software: instructions used to manipulate hardware– Requirements: input, processing, storage, output• All hardware operations are based on binary values• Binary number system consists of two digits: 0 and 1• Fundamental groupings of binary numbers:– Bit: binary digit that can take on values of 0 or 1– Nibble: four bits– Byte: eight bits By FITA AYALEW
  4. 4. Figure 1-1All communication, storage,and processing of data inside a computerare in binary form until presented as outputto the user By FITA AYALEW
  5. 5. PC Hardware Components Most input/output (I/O) devices are external to case Most processing and storage devices are internal Central processing unit (CPU)  Also called the processor or microprocessor  Reads input, processes data, writes data to storage Elements required by I/O and storage devices  A method for CPU to communicate with the device  Software to instruct and control the device  Electricity to power the device By FITA AYALEW
  6. 6. Hardware Used for Input and Output Connections to the case can be cabled or wireless Port: access point located in back or front of case Chief input devices:  Keyboard: enhanced type holds 104 keys  Mouse: pointing device used to select screen items Chief output devices:  Monitor: visually displays primary output of computer  Printer: produces output on paper (hard copy) By FITA AYALEW
  7. 7. Hardware Inside the Computer Case Most storage and processing occurs in the case Internal devices common to most computers:  Motherboard containing CPU, memory, other parts  Floppy drive, hard drive, CD drive for persistent storage  Power supply with power cords supplying electricity  Circuit boards for internal and external communication  Cables to connect devices to all circuit boards By FITA AYALEW
  8. 8. Figure 1-2 Inside the computer case By FITA AYALEW
  9. 9. The Motherboard The largest and most important circuit board  Also known as the main board or system board  Contains the CPU, expansion slots, other devices Categories used to group motherboard components  Processing, temporary storage, communication, power All devices communicate with CPU on motherboard A peripheral device links to motherboard via cable Some motherboard ports outside of the case:  Keyboard, mouse, parallel, USB ports, sound ports By FITA AYALEW
  10. 10. Figure 1-4All hardware components are either located on themotherboard or directly or indirectly connected to it because theymust all communicate with the CPU By FITA AYALEW
  11. 11. Figure 1-5 A motherboard provides portsfor common I/O devices By FITA AYALEW
  12. 12. The Processor and the Chipset CPU: chip that performs most data processing Chipset: group of microchips controlling data flow Personal computer (PC): chief focus of this text Major manufacturers of CPUs and chipsets for PCs  Intel Corporation, AMD, VIA, SiS, and Cyrix By FITA AYALEW
  13. 13. Figure 1-6This motherboard uses two chips in its chipset (notice the bus linescoming from each chip used for communication) By FITA AYALEW
  14. 14. Storage Devices Primary storage (main memory):  Temporary storage used by the processor  Example: RAM (random access memory) Secondary storage (permanent storage):  Enables data to persist after the machine is turned off  Examples: hard drive, CD, floppy disk Analogy to primary-secondary memory relationship  Book stacks in a library are like permanent storage  Books can be moved to a desk (temporary storage) By FITA AYALEW
  15. 15. Primary Storage RAM (random access memory): Device providing temporary storage Located on motherboard and on other circuit boards  Three types of RAM boards (memory modules):  DIMM (dual inline memory module)  RIMM (Rambus inline memory module)  SIMM (single inline memory module)  RAM is volatile (data does not persist)  ROM (read-only memory) is nonvolatile By FITA AYALEW
  16. 16. Figure 1-6SIMM, DIMM, or RIMM holds RAM andis mounted directly on a motherboard By FITA AYALEW
  17. 17. Secondary Storage Hard drive  Case containing disks that rotate at high speeds  An arm with a read/write head traverses the platter Integrated Drive Electronics (IDE)  Technology used internally by a hard drive ATA (AT Attachment) standard  Specifies motherboard-hard drive interface  Types: Serial ATA or parallel ATA (Enhanced IDE) Parallel ATA accommodates up to four IDE devices By FITA AYALEW
  18. 18. Figure 1-7Two IDE devices connected to a motherboardusing both IDE connections and two cable By FITA AYALEW
  19. 19. Secondary Storage …(continued) Serial ATA standard  Allows for more than four drives in a system  Applies only to hard drives and not to other drives Some IDE devices: hard drives, Zip drives, CD drive Floppy drive  3.5-inch disk holding 1.44 MB of data  Floppy drive connector is distinct from IDE connectors CD-ROM (compact disc read-only memory) drive  Standard equipment for reading software distributions By FITA AYALEW
  20. 20. Motherboard Components Used For Communication Among Devices Traces: circuits or paths that move data and power Bus: system of pathways and transmission protocols Data bus  Lines in a bus that carry the data  Binary bits correspond to voltage values of on or off  Data path sizes: 8, 16, 32, 64, or 128 bits wide Main bus on motherboard (system bus, memory bus)  Communicates with CPU, memory, and chipset Pulse of system clock carried by line on motherboard By FITA AYALEW
  21. 21. Motherboard Components Used For Communication Among Devices …(continued) Devices work according to beats (or cycles) Clock speed is measured in hertz (cycles/second)  One megahertz (MHz): one million cycles per second  One gigahertz (GHz): one billion cycles per second Common ratings for motherboard buses  1066 MHz, 800 MHz, 533 MHz, or 400 MHz Range of CPU speeds: 166 MHz to 4 GHz Buses for expansion slots: PCI, AGP, ISA By FITA AYALEW
  22. 22. Figure 1-8PCI bus expansion slots are shorter than ISA slots and offset further; the oneAGP slot is set farther from the edge of the board By FITA AYALEW
  23. 23. Interface (Expansion) Cards Some names for circuits mounted in expansion slots:  Circuit cards, adapter boards, expansion cards, cards Cards that connect the CPU to an external device:  Video: provides a port for the monitor  Sound: provides ports for speakers and microphones  Network: provides a port for a network cable  Modem: provides ports for phone lines Determine a card’s function by identifying its port By FITA AYALEW
  24. 24. Figure 1-9This circuit board is a modem card and is mounted in a PCI slot on themotherboard By FITA AYALEW
  25. 25. The Electrical System Power supply  Most important electrical component  Converts AC voltage external source to DC voltage  Reduces voltage from 110-220 volts to 12 volts or less  Runs a fan to cool the inside of the computer case Temperatures > 185° F can cause component failure Motherboard has 1 or 2 connections to power supply By FITA AYALEW
  26. 26. Figure 1-10The motherboard receives its power from the power supply by way of one or moreconnections located near the edge of the board or near the processor By FITA AYALEW
  27. 27. Instructions Stored on the Motherboard and Other Boards BIOS (basic input/output system)  Data and instructions stored on ROM chips  ROM BIOS chips are a type of firmware Three purposes served by motherboard ROM BIOS:  System BIOS: used to manage simple devices  Startup BIOS: used to start the computer  CMOS setup: used to change motherboard settings CMOS RAM: includes date, time, port configurations Flash ROM: ROM chips that can be overwritten By FITA AYALEW
  28. 28. Figure 1-11 This firmware chip contains flash ROM and CMOS RAM; CMOS RAMis powered by the coin battery located near the chip By FITA AYALEW
  29. 29. Plug and Play Also known as PnP Standard simplifying installation of hardware devices PnP BIOS begins process of configuring devices PnP-compliant operating system completes configuration ESCD (extended system configuration data) Plug and Play BIOS  Enhanced version of PnP  Stores manual configuration steps By FITA AYALEW
  30. 30. Summary A computer comprises hardware and software Main functions: input, output, processing, storage Data is stored in a binary format (1 or 0, on or off) Input/output devices: keyboard, mouse, printer, monitor Motherboard (system board): contains the CPU, access to other circuit boards and peripherals Primary storage (RAM) is volatile (temporary) Secondary storage is nonvolatile (permanent) Parallel and serial ATA standards: enable secondary storage devices to interface with the motherboard Computer bus: system of communication pathways and protocols ROM BIOS helps start PCs, manage simple devices, and change some motherboard settings By FITA AYALEW
  31. 31. CHAPTER 2Operating System Basics By FITA AYALEW
  32. 32. Objectives Learn about the various operating systems and the differences between them Learn how an OS interfaces with users, files and folders, applications, and hardware Learn about a few OS tools you can use to examine and maintain a system By FITA AYALEW
  33. 33. Operating Systems Past and Present What an operating system (OS) does:  Manages hardware  Runs applications  Provides an interface for users  Retrieves and manipulates files The OS can be analogized to a “middleman” A computer needs only one operating system Operating systems have evolved to a complex form By FITA AYALEW
  34. 34. Figure 2-1Users and applications depend on the OS: to relate to all applications andhardware components By FITA AYALEW
  35. 35. What an Operating System Does Four functions common to all operating systems:  Providing a user interface  Managing files  Managing applications  Managing hardware All OSs also have similar core components By FITA AYALEW
  36. 36. Operating System Components Components common to all OSs: shell and kernel The shell exposes functions to users and applications  Example 1: enables user to select a CD  Example 2: enables application to print a document The kernel (core) interacts with hardware devices  Example: passes a print request to a printer device Registry database and initialization files  Used to store configuration information in Windows By FITA AYALEW
  37. 37. Figure 2-2Inside an operating system, different components perform variousfunctions By FITA AYALEW
  38. 38. An OS Provides a User Interface Sequence of events occurring after PC is turned on  The operating system is loaded  Running OS provides an interface (desktop)  OS awaits an event, such as a double-click A user can initiate an event in several ways:  Click a menu item  Enter a command in Run dialog or command console  Double-click an icon By FITA AYALEW
  39. 39. An OS Manages Files and Folders File system: organizes files and folders File systems used by Windows for hard drives:  File Allocation Table (FAT): tracks disk space usage  New Technology File System (NTFS): replacing FAT Organization of a hard drive or floppy disk  Platter contains concentric tracks  Track contains 512 byte sectors  Cluster contains one or more sectors  Cluster is the smallest unit on disk for storing a file By FITA AYALEW
  40. 40. An OS Manages Applications The OS installs and runs all other PC software Application: software providing services for users Applications rely on the OS for support operations  Example: MS word relies on OS to manage memory Applications are typically tailored to a single OS  Ensure that OS is suitable for a given application By FITA AYALEW
  41. 41. An OS Manages Hardware OS interacts with hardware using drivers or BIOS Software falls into three categories:  Device drivers or the BIOS  Operating system  Application software By FITA AYALEW
  42. 42. Summary The OS manages system resources for users and Applications DOS (disk operating system): early command driven OS Modern OSs: Windows 2000/XP, Linux, Mac OS X Operating systems are divided into a kernel and user shell OS functions: providing a user interface, managing files, managing applications, and managing hardware By FITA AYALEW
  43. 43. CHAPTER 3PC Repair Fundamentals and safety precautions By FITA AYALEW
  44. 44. Objectives Learn about tools you’ll need as a PC support technician Learn how to develop a preventive maintenance plan and what to include in it Learn how to work inside a computer case Learn how to approach and solve a PC problem By FITA AYALEW
  45. 45. PC Support Technician Tools Help you maintain a computer Help you diagnose and repair computer problems Criteria for choosing tools:  Level of PC support you expect to provide  Amount of money you can spend Some essential tools:  Ground bracelet, ground mat, or ground gloves  Torx screwdriver set  Recovery CD, DVD, or floppy disk for target OS Store tools in toolbox for PC troubleshooting By FITA AYALEW
  46. 46. Figure 3-1PC support technician tools By FITA AYALEW
  47. 47. Recovery CDs Used to boot a system Also used to repair and reinstall Windows Primary recovery CD sources  PC manufacturer (preferred)  Operating system distributor, such as Microsoft Some hard drives have a hidden recovery partitions  A hidden partition can be used to reinstall Windows  A utility for creating recovery CDs may be provided  Access hidden utilities by pressing a Fn key at startup By FITA AYALEW
  48. 48. Loop-Back Plugs• Used to test various ports – Some port types: serial, parallel, USB, network• How to use a loop-back plug – Plug in the loop-back plug – Run the software that comes with the plug By FITA AYALEW
  49. 49. Cleaning Pads and Solutions Various types are designed for specific uses Example: contact cleaner  Cleans contacts on expansion cards Warning: solutions may be flammable and/or toxic Sources of safety and emergency instructions:  Side of the can of solution  Material safety data sheet (MSDS) Adhere to safety procedures of your employer  Example: fill out an accident report (if required) By FITA AYALEW
  50. 50. Post Diagnostic Cards Report computer errors and conflicts at POST How to use a POST diagnostic card:  Install card in an expansion slot on the motherboard  Attempt to boot your system  Record any error codes appearing in LED panel  Look up the entry associated with the error code Examples of Post diagnostic cards:  PCI Error Testing/Debug Card by Winic Corporation  POST card V3 by Unicore Software, Inc.  Post Code Master by MSD, Inc. By FITA AYALEW
  51. 51. Figure 3-2Post Code Master diagnostic card by MSD, Inc. By FITA AYALEW
  52. 52. Personal Computer Preventive Maintenance Preventive maintenance reduces number of problems Goals of preventive maintenance plans:  Prevent failures  Reduce repair costs  Reduce downtimes Goal of disaster recovery plan: manage failures Some causes of PC failure: heat, dust, spills, viruses By FITA AYALEW
  53. 53. When a PC is your Permanent Responsibility Tasks and procedures to prepare for troubleshooting  Keep good backups of data and system files  Document all setup changes, problems, and solutions  Protect the system against viruses and other attacks  Always use a firewall (software or hardware barrier)  Install and run antivirus software  Keep Windows Updates current  Physically protect your equipment By FITA AYALEW
  54. 54. Creating a Preventive Maintenance Plan Plan based on history or pattern of malfunctions  Example: PCs in dusty areas need more maintenance Goals common to maintenance plans  Extend the working life of a PC  Anticipate problems that could disrupt service  Ensure data is secure and backed up  Provide support to PC users Basic steps involved in designing a plan  Define your overall goals  Incorporate procedures for achieving goals By FITA AYALEW
  55. 55. Dealing with Dust Dust accumulates in layers over components Two major problems due to dust blankets  PC components directly overheat  Cooling fans jam, also resulting in overheating Maintenance task: remove the layer of dust Two tools used to remove dust:  Antistatic vacuum  Compressed air By FITA AYALEW
  56. 56. How to Work Inside a Computer Case Objective: dismantle a computer, put it back together Some safety precautions to follow:  Make notes that will help you backtrack  Keep screws and spacers orderly  Do not stack boards on top of each other  Do not touch the chips on circuit boards  Do not use a graphite pencil to change DIP settings  Turn off the power, unplug and ground the computer  Do not remove covers of monitors or power supplies  Keep components away from hair and clothing By FITA AYALEW
  57. 57. Static Electricity Build-up of charge due to absence of conductors Electrostatic discharge (ESD)  Due to dissimilar electrical surfaces making contact  Only 10 volts of ESD can damage PC components  Walking across carpet generates up to 12,000 volts Two types of damage: catastrophic and upset failure Tool and methods for grounding yourself and the PC  Ground bracelet, ground mats, static shielding bags, antistatic gloves By FITA AYALEW
  58. 58. Figure 3-3A ground bracelet, which protects computer components from ESD, can clip tothe side of the computer case and eliminate ESD between you and the case By FITA AYALEW
  59. 59. Steps to Take Apart a Computer Essential tools:  Ground bracelet  Phillips-head screwdriver  Flat-head screwdriver, paper, and pen Follow safety precautions at all times Summary of Steps 1 – 4  1. Enter CMOS and write down customized settings  2. Power down the system, unplug all components  3. Put the computer on a good-sized table  4. Remove the cover of the PC By FITA AYALEW
  60. 60. Figure 3-4Removing the cover By FITA AYALEW
  61. 61. Steps to Take Apart a Computer (continued) Summary of steps 5 - 11  5. Diagram cable connections and switch settings  6. Identify cables connecting drives to motherboard  7. Remove the cables to all drives  8. Remove the expansion cards  9. Remove the motherboard (or drives)  10. Remove the power supply from the case  11. Remove each drive (if not already removed) By FITA AYALEW
  62. 62. Figure 3-5Remove the motherboard from the case By FITA AYALEW
  63. 63. Steps to Put a Computer Back Together1. Install power supply, drives, motherboard, cards2. Connect all data and power cables3. Plug in the keyboard, monitor, and mouse4. Ask instructor to check work (if in a classroom)5. Turn on the power and check PC functions By FITA AYALEW
  64. 64. Fundamental Rules for PC Troubleshooting Approach the problem systematically Divide and conquer Don’t overlook the obvious Check the simple things first Make no assumptions Become a researcher Write things down Reboot and start over Establish your priorities Don’t assume the worst Know your starting point By FITA AYALEW
  65. 65. Figure 3-6General approach to troubleshooting By FITA AYALEW
  66. 66. Summary Some PC repair tools: recovery CDs, screwdrivers, POST, cleaning pads and solutions, diagnostic cards Preventive maintenance plans extend the life of a PC Follow an organization’s preventive maintenance plan, or develop one if it does not exist Computers present chemical and electrical hazards Protect components in case from ESD by grounding yourself and the PC Assembling and reassembling a PC prepares the technician for actual repair work Expert troubleshooters ask good questions Before tackling a problem, develop a game plan By FITA AYALEW
  67. 67. PC maintenance andTroubleshooting Chapter 4 Computer Case, Electricity, and Power Supplies By FITA AYALEW
  68. 68. Objectives Select an appropriate case for a PC Understand electrical basics Select an appropriate power supply Troubleshoot a PC using electrical testing Select appropriate power conditioning and backup devices By FITA AYALEW
  69. 69. Case Form FactorsATX:– Loose wires coming from powerswitch, will connect tomotherboard later– Bezel for the motherboard’sbuilt-in I/O ports in back By FITA AYALEW
  70. 70. Case Form Factors• AT:– Power switch connects topower supply– Slots in case floor forplastic standoffs By FITA AYALEW
  71. 71. Towers and Desktop casesFigure 4-1Towers and Desktop Cases By FITA AYALEW
  72. 72. Measures and Properties of Electricity Successful PC technicians:  Understand electricity  Know how to use electricity  Know how to measure electricity  Can protect computer equipment from electricity Units used to measure characteristics of electricity  Volt, amp, ohm, and watt By FITA AYALEW
  73. 73. Electricity Basics Voltage  Difference in charge between the positive and negative poles  Can be positive or negative volts (v)  Ordinary household current is 110v in the USA, or 220v in most of Europe By FITA AYALEW
  74. 74. AC and DC AC: Alternating Current  Ordinary household current  Alternates positive and negative poles at 60 Hz  Good for sending power over long distances DC: Direct current  Batteries  Positive and negative poles stay fixed  Lower overhead By FITA AYALEW
  75. 75. Some Common Electric Components Materials used to make components:  Conductors: weakly resist flow of current; e.g., copper  Insulators: highly resist flow of current; e.g., ceramics  Semiconductors: allow flow if charged; e.g., silicon Transistor  Used to switch current on (1) and off (0)  Also used to amplify current  Made of three layers of semiconductor material  Charge applied to center layer controls switching Capacitor  Holds electrical charge for a period of time  Used to create even flow of current in a PC Diode  Allows electricity to flow in one direction only  Used to rectify current (convert AC to DC) Resistor  Controls the amount of current flowing through By FITA AYALEW
  76. 76. Electrical Measurements• Analog multimeter • Uses a needle gauge • Continuously variable• Digital multimeter • Uses a digital display • Precise values • More suitable for computers By FITA AYALEW
  77. 77. Measuring Voltage• Must be measured withcomputer on• Use back-probing• Place black probe ongrounding wire (black)• Place red probe on By FITA AYALEW
  78. 78. Types of Power Supplies• Form factor AT ATX Other sizes• Wattage By FITA AYALEW
  79. 79. AT Power Supply P8 and P9 connectors to motherboard Power switch attached directly +5v, -5v, +12v, and -12v power By FITA AYALEW
  80. 80. AT Connectors Figure 4-2 AT Connectors By FITA AYALEW
  81. 81. ATX Power Supply Single 20-wire connector to motherboard No direct connection to power switch +5v, -5v, +12v, -12v, and +3.3v power By FITA AYALEW
  82. 82. ATX Power Supply Wires By FITA AYALEW
  83. 83. Power Supply Connectors • Molex – Used for most drive types • Mini – Used for 3.5” floppy drives By FITA AYALEW
  84. 84. Determining Wattage Requirements Read label on power supply Calculate wattage drawn by each component Compare total amount drawn to label By FITA AYALEW
  85. 85. Computer Power Consumption Component Requirement Component Requirement Line(s) Component Requirement Line(s) Used Line(s) Used UsedAGP Video Card 30 - 50W +3.3V AGP Video Card 30 - 50W +3.3V AGP Video Card 30 - 50W +3.3VAMD Athlon Processor 70W +12V Pentium 4 Processor 70W +12V Pentium III Processor 38W +5VRAM 8W per 128MB +3.3V Motherboard (w/o CPU or RAM) 25 - 40W +3.3V and +5V Case/CPU Fans 3W +12V10,000rpm SCSI Drive 10 - 40W +5V and +12V 7200rpm IDE Hard Drive 5 - 20W +5V and +12V CD-RW 10 - 25W +5V and +12VDVD-ROM 10 - 25W +5V and +12V CD-ROM 10 - 25W +5V and +12V Floppy Drive 5W +5VSCSI Controller PCI Card 20W +3.3V and +5V 10/100 NIC 4W +3.3V Average PCI Card 5 - 10W +5VAMD Athlon Processor 70W +12V Pentium 4 Processor 70W +12V Pentium III Processor 38W +5VRAM 8W per 128MB +3.3V Motherboard (w/o CPU or RAM) 25 - 40W +3.3V and +5V Case/CPU Fans 3W +12V10,000rpm SCSI Drive 10 - 40W +5V and +12V 7200rpm IDE Hard Drive 5 - 20W +5V and +12V CD-RW 10 - 25W +5V and +12VDVD-ROM 10 - 25W +5V and +12V CD-ROM 10 - 25W +5V and +12V Floppy Drive 5W +5VSCSI Controller PCI Card 20W +3.3V and +5V 10/100 NIC 4W +3.3V Average PCI Card 5 - 10W +5VAMD Athlon Processor 70W +12V Pentium 4 Processor 70W +12V Pentium III Processor 38W +5VRAM 8W per 128MB +3.3V Motherboard (w/o CPU or RAM) 25 - 40W +3.3V and +5V Case/CPU Fans 3W +12V10,000rpm SCSI Drive 10 - 40W +5V and +12V 7200rpm IDE Hard Drive 5 - 20W +5V and +12V CD-RW 10 - 25W +5V and +12VDVD-ROM 10 - 25W +5V and +12V CD-ROM 10 - 25W +5V and +12V Floppy Drive 5W +5VSCSI Controller PCI Card 20W +3.3V and +5V 10/100 NIC 4W +3.3V Average PCI Card 5 - 10W +5V By FITA AYALEW
  86. 86. Failed Power Supply Fan won’t spin Inconsistent power provided (fan revs and sags) System will not boot (appears dead) Typically overloads at startup Problems occur when drives spin up System may spontaneously reboot when multiple drives are accessed By FITA AYALEW
  87. 87. Problems with the Power Supply Fan Defective fans usually hum before they stop working Response to diagnosis of defective fan  Replace fan or the entire power supply If replacement does not work, suspect another short Do not operate a PC if the fan does not work  Computers will overheat, damaging circuit boards Indirect sources of fan problems:  Shorts in drives, motherboard, or expansion cards By FITA AYALEW
  88. 88. Problems with Overheating Causes intermittent problems May also cause the system to reboot or not boot Temperature in a case should not exceed 100° F Some possible solutions:  Remove dust from power supply, vents, heat sink  Secure cables and cords with tie wraps  Install another exhaust fan on the rear of the case  Install a fan in expansion slot next to video card  Replace component that is damaged By FITA AYALEW
  89. 89. Replacing the Power Supply The power supply is a field replaceable unit (FRU) Criteria for replacement power supply to meet:  Uses the correct form factor  Adequately rated for power in watts  Has all power connectors needed by your system Before replacing power supply, test new device  Connect components to new power supply  Turn on PC and observe whether problem is solved  If problem is solved, perform replacement procedure By FITA AYALEW
  90. 90. Summary Form factor: specifies size, shape, features of device Motherboard, power supply, and case share the same form factor, such as ATX Three types of cases: desktop, tower, and notebook Quantities that characterize electricity: voltage, current, resistance, power Current flows from hot wires to neutral wires; excess current escapes through grounds AC supplied by power station is transformed and rectified before flowing into the PC Major components in a circuit board: transistor, capacitor, diode, Resistor Electrical threats: ESD, EMI, uneven current flow, sudden power surges (or spikes) By FITA AYALEW
  91. 91. CHAPTER 5Processors and Chipsets By FITA AYALEW
  92. 92. Objectives Learn about the many different processors used for personal computers and notebook computers Learn about chipsets and how they work Learn how to keep a processor cool using heat sinks and coolers Learn how to install and upgrade a processor By FITA AYALEW
  93. 93. Introduction The processor and chipset  Most important components on the motherboard The chipset is embedded in the motherboard Processor and chipset are located on motherboard  Components determine power and features of system Major manufacturers: Intel, AMD, and Cyrix Factors used to rate processors:  System bus speeds supported; e.g., 1066 MHz  Processor core frequency in gigahertz; e.g., 3.2 GHz  Word size (32 or 64 bits) and data path (64 or 128 bits)  Multiprocessing ability and processor specific memory  Type of RAM, motherboard, and chipset supported By FITA AYALEW
  94. 94. How a Processor Works Three basic components:  Input/output (I/O) unit  Control unit  One or more arithmetic logic units (ALUs) Registers: high-speed memory used by ALU Internal cache: holds data to be processed by ALU Two types of buses:  External (front-side) bus: data portion is 64 bits wide  Internal (back-side) bus: data portion is 32 bits wide By FITA AYALEW
  95. 95. Figure 5-1 Since the Pentium processor was first released in 1993, the standardhas been for a processor to have two arithmetic logic units so that it can process twoinstructions at once By FITA AYALEW
  96. 96. How a Processor Works (continued) System bus frequency or speed  Faster than other buses; e.g., 1066 MHz, 800 MHz Processor frequency or speed  Refers to speed of internal operations; e.g., 3.2 GHz  System bus frequency x multiplier = processor frequency  Overclocking: running processor at excessive speed  Throttling: decreasing speed when overheating occurs Data path size and word size  Data path: transports data into processor  Word path: number of bits processed in one operation By FITA AYALEW
  97. 97. How a Processor Works (continued) Multiprocessing  Simultaneous processing by two or more ALUs Multiprocessor platform  Contains two or more processors Dual-core processing  Processors share system bus, but have separate cache Memory cache  Static RAM (SRAM): holds data as long as power is on  Lets processor bypass slower dynamic RAM (DRAM)  L1 cache is on the processor chip, L2 cache is external By FITA AYALEW
  98. 98. Figure 5-2 AMD dual-core processing using two Opteron inthe single processor housing By FITA AYALEW
  99. 99. Figure 5-3 Cache memory (SRAM) is used to temporarily holddata in expectation of what the processor will request next By FITA AYALEW
  100. 100. Processor Sockets and Slots Used to connect the processor to the motherboard Motherboard type must match processor package Types of sockets  Sockets are built around pin grid or land grid arrays Variations: PGA, SPGA, LGA, DIP, LIF, and ZIF Types of slots  Packages fit into slots like expansion cards Designated slots: Slot 1, Slot A, and Slot 2  New processor packages use sockets, not slots  Slocket: adapts Slot 1 to processor requiring a socket By FITA AYALEW
  101. 101. Figure 5-4 Socket LGA775 is the latestIntel socket By FITA AYALEW
  102. 102. Figure 5-5 A riser card can be used to install a Celeronprocessor into a motherboard with slot 1 By FITA AYALEW
  103. 103. The Chipset Set of chips on the motherboard Controls memory cache, external buses, peripherals Intel dominates the market for chipsets  Example: i800 series of chipsets Intel 800 series Accelerated Hub Architecture  All I/O buses connect to a hub interface  The hub connects to the system bus  North Bridge: contains graphics and memory controller  South Bridge: contains I/O controller hub  Each bridge is controlled by a separate chipset By FITA AYALEW
  104. 104. Figure 5-6 Using Intel 800 series Accelerated Hub Architecture, ahub interface is used to connect slower I/O buses to the system bus By FITA AYALEW
  105. 105. Heat Sinks and Cooling Fans Cooling assembly should keep temperatures <185° F Target temperature range: 90° - 100° F  One or more fans are needed to meet cooling needs Cooling fan sits on top of processor with wire or clip Heat sink: clip-on device pulling heat from processor Cooler: combination of heat sink and cooling fan By FITA AYALEW
  106. 106. Voltage to the Processor Earlier processors drew power from system bus lines  Newer motherboards may have a power connector Modern motherboards regulate voltage to socket Sockets were more universal for older processors  Processor may fit socket, but not get correct voltage  Ensure that motherboard supports older processor Dual-voltage processor  Voltages for internal and external operations differ Single-voltage processor: requires only one voltage By FITA AYALEW
  107. 107. Figure 5-7 Auxiliary 4-pin power cord from the powersupply connects to the ATX12V connector on the motherboard toprovide power to the Pentium 4 By FITA AYALEW
  108. 108. Summary Basic CPU components: I/O unit, control unit, ALUs Registers: high speed memory used by ALU in current processing Internal cache: holds frequently used instructions Types of buses in CPU: internal and external (system) Processors are housed inside a processor package Processors fit into slots or sockets in the motherboard The chipset controls memory cache, external buses and some peripherals A cooler comprises a cooling fan and a heat sink A voltage regulator module (VRM) controls the amount of voltage to a processor By FITA AYALEW
  109. 109. CHAPTER 6Motherboards By FITA AYALEW
  110. 110. Objectives Learn about the different types of motherboards and how to select one Learn how to support and configure a motherboard Learn how to install or replace a motherboard Learn how to troubleshoot a motherboard and processor By FITA AYALEW
  111. 111. Selecting a Motherboard Motherboard form factor  Determines the size of the board  Drives selection of power supply, case, CPU, cards ATX: most popular motherboard form factor BTX: the latest motherboard form factor Three types of motherboards you can select:  A board providing the most room for expansion  A board suiting the computer’s current configuration  A board falling in between current and future needs By FITA AYALEW
  112. 112. Figure 6-1 An ATX motherboard with PCI Express andSocket 775 By FITA AYALEW
  113. 113. Selecting a Motherboard (continued) Some questions to ask when picking a motherboard  What form factor does the motherboard use?  Does the motherboard provide proper CPU support?  What type of BIOS does the motherboard use?  Does the board fit the case you plan to use?  What is the warranty on the board? Embedded (on-board) component  Component located on the board  Avoid board with too many embedded components  Such boards do not easily accept add-on devices By FITA AYALEW
  114. 114. Configuring and Supporting a Motherboard Components that require configuration and support:  Expansion slots  Internal and external connectors Expansion slots are supported by buses  Before configuring slots, learn about buses Buses are like highway transportation systems  Facilitate communication among devices Four types of cargo carried by a bus:  Power,  control signals,  memory addresses,  data By FITA AYALEW
  115. 115. Figure 6-2 How PCI Express connects to thechipset and processor By FITA AYALEW
  116. 116. Hardware Configuration (continued) CMOS setup program  Can be accessed without opening the case  Stored on a floppy disk or ROM BIOS chip  Access built-in program by pressing key during POST  Menus: Main, Advanced, Power, Boot, and Exit  Brand name PCs, such as IBM, have custom screens By FITA AYALEW
  117. 117. Table 6-1 How to access CMOS setup By FITA AYALEW
  118. 118. Figure 6-2 CMOS Setup Main menu By FITA AYALEW
  119. 119. Hardware Configuration (continued) Battery power to CMOS  Enables CMOS to hold data after the PC is turned off  Setup information is lost if battery fails or disconnects Startup passwords in CMOS  Stored in CMOS and changed in setup screen  Should be distinguished from OS passwords CMOS settings are specified in motherboard manuals Documentation of configuration settings  Enables you to recapture lost or altered settings  Should be labeled and stored in a safe place By FITA AYALEW
  120. 120. Flashing ROM BIOS Programs stored in the ROM BIOS chip:  CMOS setup program  Startup BIOS that manages the startup process  System BIOS that manages basic I/O functions Programs on ROM BIOS may need upgrades Flashing: upgrading or refreshing ROM BIOS chip Sources for ROM BIOS upgrades  Manufacturer’s Web site By FITA AYALEW
  121. 121. Replacing a Motherboard Overview of the replacement process 1. Verify that you have selected the right motherboard 2. Determine the power configuration settings 3. Remove components to reach the old motherboard 4. Set any jumpers or switches on the motherboard 5. Install the processor and processor cooler 6. Install RAM into appropriate slots on motherboard 7. Install the motherboard 8. Attach cabling (case switches, power supply, drives) 9. Install the video card on the motherboard By FITA AYALEW
  122. 122. Replacing a Motherboard (continued) Overview of the replacement process (continued) 10. Plug in PC and then attach monitor and keyboard 11. Boot the system and enter CMOS setup 12. Make sure the settings are set to default 13. Observe POST and verify that no error occurs 14. Check for conflicts with system resources 15. Install the motherboard drives 16. Install any other expansion cards and drives 17. Verify the system is up and running By FITA AYALEW
  123. 123. Installing the Motherboard in the Case Overview of the eight general steps: 1. Install the faceplate (I/O shield) 2. Install the standoffs (spacers) 3. Secure the motherboard in the case 4. Connect the power cord to the PI power connection 5. Connect 4-pin auxiliary power cord to motherboard 6. Connect the wire leads from front panel of case 7. Refer to manual to verify wire to pin connection 8. Connect USB connection (if present) to USB ports By FITA AYALEW
  124. 124. Completing the Installation Following the connection of cables and cords  Install the video card  Plug in the keyboard and monitor  Turn the system on  Look out for errors during POST  Install drivers from CD bundled with motherboard  Verify operations  Make OS and CMOS adjustments as needed By FITA AYALEW
  125. 125. Problems with Installations If CPU was added to working motherboard, check:  Thermal paste between CPU and heat sink  Fastening between cooler and motherboard frame  Pins or lands on the socket and processor Things to check if new motherboard is not working:  Whether the front cover of the case is installed  Whether the power switch on back of the case is on  Incorrect connections  Installation of CPU, thermal compound, and cooler  Installation of all motherboard drivers on the CD By FITA AYALEW
  126. 126. Summary Motherboard form factor drives selection of motherboard Configurable components: bus, expansion slots, other connectors Cargo carried by a computer bus: electrical power, control signals, memory address, data Bus types: local, local video, local I/O, expansion The CMOS setup program is stored on a floppy disk or ROM BIOS chip Document configuration settings for recovery needs Upgrade ROM BIOS using a technique called flashing Use POST reporting to help diagnose problems By FITA AYALEW
  127. 127. CHAPTER 7Upgrading Memory By FITA AYALEW
  128. 128. Objectives Learn about the different kinds of physical memory and how they work Learn how to upgrade memory Learn how to troubleshoot problems with memory Memory technologies have evolved rapidly Study development to grasp current technology Memory-related tasks performed by a PC technician  Upgrading memory  Adding more memory to a system  Troubleshooting problems with memory By FITA AYALEW
  129. 129. RAM Technologies RAM (random access memory)  Holds data and instructions used by CPU  Volatile (data does not persist after PC is turned off) ROM (read-only memory)  In firmware on motherboard; e.g., ROM BIOS  Non-volatile (retains data after PC is turned off) Reviewing other salient features of RAM  RAM is stored in modules: DIMMs, RIMMs, SIMMs  Types: static RAM (SRAM) and dynamic RAM (DRAM)  Memory cache is made up of SRAM (it is faster) By FITA AYALEW
  130. 130. Figure 7-1 DRAM on most motherboards today is stored onDIMMs By FITA AYALEW
  131. 131. RAM Technologies (continued) Differences among DIMM, RIMM, and SIMM modules  Width of the data path each module accommodates  The way data moves from system bus to the module Older DRAM worked asynchronously with system bus Newer DRAM works synchronously with system bus  Retrieves data faster as it keeps time with system clock Goal of each new technology  Increase overall throughput while retaining accuracy By FITA AYALEW
  132. 132. Figure 7-2 Types of memory modules By FITA AYALEW
  133. 133. SIMM Technologies SIMMS have a 32-bit data path Speeds (access times): 60, 70, 80 nanoseconds (ns)  Smaller number indicates greater speed Components making up the access time  Processor requests the data  Memory controller locates data on the SIMM  Data is placed on the memory bus  The processor reads the data off the bus  Memory controller refreshes memory chip on SIMM By FITA AYALEW
  134. 134. DIMM Technologies DIMM (dual inline memory module)  Has independent pins on opposite sides of module  Can have memory chips on one or two sides  Has 168, 184, or 240 pins on edge connector  Has a 64-bit data path and holds 8 MB - 2 GB RAM Synchronous DRAM (SDRAM)  Has two notches, and uses 168 pins DDR (Double Data Rate) and DDR2 DIMM  DDR SDRAM runs 2 x faster than regular SDRAM  DDR2 SDRAM is faster than DDR, uses less power By FITA AYALEW
  135. 135. Table 7-1General approach to troubleshooting By FITA AYALEW
  136. 136. Figure 7-3 Using dual channels, the memory controller canread from two DIMMs at the same time By FITA AYALEW
  137. 137. How to Upgrade Memory The basic technique: add more RAM modules Problems solved with new memory:  Slow performance  Applications refusing to load  An unstable system Note empty memory slots on most new computers  Accommodate new DIMM or RIMM By FITA AYALEW
  138. 138. How Much and What Kind of Memory to Buy Questions to ask before performing an upgrade:  How much memory do I need?  How much RAM is currently installed in my system?  How many memory modules are currently installed?  What kind of memory modules are currently installed?  How much memory can I fit on my motherboard?  What kind of memory can I fit on my motherboard?  How do I select and purchase the right memory? Refer to system utilities to determine capacity Motherboard documentation guides choice of add-ons By FITA AYALEW
  139. 139. Installing Memory Follow safety procedures when installing RAM  Example: always use a ground bracelet as you work Installing SIMMs  Module slides into slot at an angle  Make sure each module is secured to slot  Verify that POST memory count includes new module Installing RIMMs  Install modules in this order: bank 0, bank 1  Remove the RIMM (placeholder) filling the slot  Use notches to help orient module in the socket By FITA AYALEW
  140. 140. Installing Memory (continued) Installing DIMMs  Pull out the supporting arms on the sides of the slot  Use notches on the DIMM edge connector as a guide  Insert the DIMM straight down into the slot  Ensure that supporting arms lock into position New installations are generally uncomplicated  Usually involves just placing memory on motherboard Older computers may need change to CMOS setup If new memory not recognized, try reseating device By FITA AYALEW
  141. 141. Upgrade Problems Dealing with unrecognized add-on or error message  Remove and reinstall the module  Check for the suitability of the module for the board  Ensure that the module is the correct size  Remove the module and check for error message  Test the module in another socket  Clean the module edge connectors  Try flashing BIOS By FITA AYALEW
  142. 142. Recurring Problems Symptoms of an unreliable memory:  The system locks up  Error messages about illegal operations often display  General Protection Faults occur during normal operation Some troubleshooting tasks  Run updated antivirus software to check for viruses  Replace memory modules one at a time  Try uninstalling the new hardware  Test, reseat, or replace RAM  Verify that virtual memory settings are optimized By FITA AYALEW
  143. 143. Summary RAM categories: static RAM (SRAM), dynamic RAM (dRAM) Modules used to store DRAM: SIMM, DIMM, RIMM Synchronous DRAM (SDRAM): moves to the beat of the system clock Simple parity checks identify one corrupted bit Error correcting code (ECC) detects and corrects one flipped bit By FITA AYALEW
  144. 144. Summary (continued) Memory speeds are measured in ns, MHz, PC rating When upgrading memory, use the type, size, and speed the motherboard supports New modules should match those already installed Install new modules by inserting them into the appropriate slots When troubleshooting, first try the simple technique of reseating the module By FITA AYALEW
  145. 145. CHAPTER 8Hard Drives By FITA AYALEW
  146. 146. Objectives Learn how the organization of data on floppy drives and hard drives is similar Learn about hard drive technologies Learn how a computer communicates with a hard drive Learn how to install a hard drive Learn how to solve hard drive problems By FITA AYALEW
  147. 147. Introduction Hard drive: most important secondary storage device Hard drive technologies have evolved rapidly  Hard drive capacities and speeds have increased  Interfaces with the computer have also changed Floppy disk will be presented before hard drives  Floppy disk is logically organized like a hard drive Practical applications:  Managing problems occurring during drive installation  Troubleshooting hard drives after installation By FITA AYALEW
  148. 148. How Hard Drives Work Components of a hard drive:  One, two, or more platters (disks)  Spindle to rotate all disks  Magnetic coating on disk to store bits of data  Read/write head at the top and bottom of each disk  Actuator to move read/write head over disk surface  Hard drive controller: chip directing read/write head Head (surface) of platter is not the read/write head Physical organization includes a cylinder  All tracks that are the same distance from disk center By FITA AYALEW
  149. 149. Figure 8-1 Inside a hard drive case By FITA AYALEW
  150. 150. Tracks and Sectors on the Drive Tracks on older drives held the same amount of data Newer drives use zone bit recording  Tracks near center have smallest number sectors/track  Number of sectors increase as tracks grow larger  Every sector still has 512 bytes  Sectors identified with logical block addressing (LBA) By FITA AYALEW
  151. 151. Figure 8-2 Floppy drives and older hard drives use aconstant number of sectors per track By FITA AYALEW
  152. 152. Figure 8-3Zone bit recording can have more sectorsper track as the tracks get larger By FITA AYALEW
  153. 153. Drive Capacity for Today’s Drives The OS reports the capacity of hard drives Accessing capacity data using Windows Explorer  Right-click the drive letter  Select Properties on the shortcut menu Calculating total capacity if drive is fully formatted  Record capacity of each logical drive on hard drive  Add individual capacities to calculate total capacity Reporting total capacity (regardless of formatting)  Windows 2000/XP: use Disk Management  Windows 9x: use Fdisk By FITA AYALEW
  154. 154. Hard Drive Interface Standards Facilitate communication with the computer system Several standards exist:  Several ATA standards  SCSI  USB  FireWire (also called 1394)  Fibre Channel The various standards will be covered By FITA AYALEW
  155. 155. Figure 8-4 A PC’s hard drive subsystem usingparallel ATA By FITA AYALEW
  156. 156. Figure 8-5 A hard drive subsystem using the new serialATA data cable By FITA AYALEW
  157. 157. How to Select a Hard Drive Hard drive must match OS and motherboard BIOS uses auto detection to prepare the device  Drive capacity and configuration are selected  Best possible ATA standard is part of configuration Selected device may not supported by BIOS Troubleshooting tasks (if device is not recognized)  Flash the BIOS  Replace the controller card  Replace the motherboard By FITA AYALEW
  158. 158. Problems with Hard Drive Installations CMOS setup does not reflect new hard drive  Solution: Enable autodetection and reboot system Error message: “ Hard drive not found.”  Reseat the data cable and reboot the PC Error message: “No boot device available.”  Insert bootable disk and restart the machine Error message 601 appears on the screen  Connect the power cord to the floppy disk drive Error message: “Hard drive not present”  Restore jumpers to their original state By FITA AYALEW
  159. 159. Problems with Hard Drive Installations (continued) • Things to check if CMOS setup does not show drive  Does your system BIOS recognize large drives?  Is autodetection correctly configured in CMOS setup?  Are the jumpers on the drive set correctly?  Are the power cord and data cable connected? By FITA AYALEW
  160. 160. How to Approach a Hard DriveProblem After the Installation Some post-installation problems  Corrupted data files  A corrupted Windows installation  A hardware issue preventing system from booting Preparation steps  Start with the end user: conduct an interview  Prioritize what you have learned  Example: make data backup your first priority  Be aware of available resources  Ex amples: documentation, Internet, Technical Support By FITA AYALEW
  161. 161. Hard Drive Hardware Problems Causes of problems present during boot:  Hard drive subsystem  Partition table  File system on the drive  Files required for the OS to boot Some things to do if POST reveals problem  Check the jumper settings on the drive  Check the cable for frayed edges or other damage  Try booting from another media; e.g. setup CD  Check manufacturer Web site for diagnostic software By FITA AYALEW
  162. 162. Hard Drive Hardware Problems (continued) Bumps are bad  A scratched surface may cause a hard drive crash  Data may be recovered, even if drive is inaccessible Invalid drive or drive specification  System BIOS cannot read partition table information  Boot from recovery CD and check partition table  To be covered in later chapters Bad sector errors  Problem due to fading tracks and sectors  Solution: replace the drive By FITA AYALEW
  163. 163. CHAPTER 9Installing and Supporting I/O Devices By FITA AYALEW
  164. 164. Objectives Learn about the general approaches you need to take when installing and supporting I/O devices Learn about keyboards Learn how to work with the mouse and other pointing devices Learn about monitors and video cards and how they relate to the system Learn how to use ports and expansion slots for addon devices Learn how to troubleshoot I/O devices, including keyboards, pointing devices, and video By FITA AYALEW
  165. 165. Basic Principles to Support I/O Devices Internal devices: hard drives, CD drives, Zip drives External devices: keyboards, monitors, mice  Connected using port off motherboard or expansion card Fundamental principles and concepts:  Every I/O device is controlled by software (device driver)  Manufacturer is best guide for installation and support  Some devices are manipulated with application software  Problems can sometimes be solved with driver  Learning about I/O devices is a moving target By FITA AYALEW
  166. 166. The Mouse and Other Pointing Devices Pointing device  Allows you to move a pointer on the screen  Enables you to perform tasks; e.g., click a button Common pointing devices  Mouse, trackball, touch pad Some mice are wireless and come with key pads  Wireless connection made through a USB receiver By FITA AYALEW
  167. 167. Mouse Technologies How the wheel mouse works  Ball internal to mouse moves as you drag mouse  Two rollers are turned by the movement of the ball  Rollers represent x (horizontal) and y (vertical) position  Each roller turns a wheel, which chops a light beam  Chops encode movement, which is passed to CPU The optical mouse  Ball replaced with microchip, laser light, and camera  Light illumines surface and camera takes snapshots  Microchip reports small changes to the PC By FITA AYALEW
  168. 168. Mouse Technologies (continued) Mouse buttons or scroll wheel are programmed Methods used by a mouse to connect to a PC  The round PS/2 mouse port off the motherboard  Bus card  A serial port  A USB port  Y-connection with the keyboard  Cordless technology Connection methods require varying resources  Motherboard mouse is the first choice By FITA AYALEW
  169. 169. Other Pointing Devices Trackball  An upside-down wheel mouse  Move the ball on top to turn rollers  Rollers turn a wheel sensed by a light beam Touch pad  Allows you to duplicate the mouse function  Move pointer by applying light pressure with one finger  Depressed pad senses the x, y movement  Buttons on the touch pad are like mouse buttons Use touch pads or trackballs where space is limited Include barcode readers, fingerprint readers, others By FITA AYALEW
  170. 170. Monitors Monitor: the primary output device of a computer Video card (controller, or adapter)  Interfaces monitor with motherboard components Two categories:  CRT (cathode-ray tube)  LCD (liquid crystal display); also called flat panel How a CRT monitor works:  Filaments shoot electron beam to front of tube  Plates direct beam to paint screen from left to right  Control grid specifies coloring of each dot on screen  Controls one of three electron guns (red, green, blue)  Modified beam strikes phosphor to produce color By FITA AYALEW
  171. 171. Figure 9-17 How a CRT monitor works By FITA AYALEW
  172. 172. Monitors (continued) Comparing features of LCD and CRT monitors:  Space: LCD requires less space than CRT monitor  Power: LCD requires less electricity to operate  Expense: LCD monitors are more expensive  Refresh rate: LCD response time < CRT refresh rates  Interlacing CRT monitors draw screen in two passes  Dot pitch: distance between color dots  Resolution: measures number of addressable pixels  Example 1: XGA supports up to 1024 x 768 pixels  Example 2: SVGA supports up to 800 x 600 pixels By FITA AYALEW
  173. 173. Video Cards Interface between monitor and computer Also called graphics adapters and video boards Five ports for five methods of data transfer:  RGB (red, green, blue) video using a VGA port  DVI (Digital Visual Interface): used by LCD monitors  Composite video: RGB mixed in the same signal  S-Video (Super-Video): sends two signals over cable  HDMI (High-Definition Multimedia Interface) Two main features: bus used and RAM supported By FITA AYALEW
  174. 174. Figure 9-1 This ATI Radeon video card has three ports forvideo out: DVI, S-Video, and the regular VGA port By FITA AYALEW
  175. 175. Figure 9-2 Rear of computer case showing ports; only the video ports are notcoming directly off the motherboard By FITA AYALEW
  176. 176. Troubleshooting Keyboards A few keys don’t work  Check the Num Lock key The keyboard does not work at all  Check the cabling Key continues to repeat after being released  Clean the key switch with contact cleaner Keys produce wrong characters  If problem is due to a bad chip, replace the keyboard Major spills on the keyboard  Try rinsing keyboard in water; reinstall after it dries By FITA AYALEW
  177. 177. Troubleshooting Monitors and Video Cards Power light (LED) does not go on; no picture  Verify that connection is tight and PC is turned on Power light (LED) is on, no picture on power-up  Check contrast, brightness or backlight adjustment Power light (LED) is on, wrong characters displayed  Exchange the video or motherboard Monitor flickers, has wavy lines, or both  Check the cabling and the refresh rate No graphics display or screen goes blank  Replace video card or add video RAM By FITA AYALEW
  178. 178. Figure 9-3 To reduce monitor flicker, increase the screenrefresh rate By FITA AYALEW
  179. 179. Troubleshooting Monitors and VideoCards (continued) Screen goes blank after 30 seconds  Check configuration of power management Poor color display  Exchange video cards or add more video RAM Picture out of focus or out of adjustment  Check adjustment knobs or change refresh rate Cracking sound  Trained technician should vacuum inside monitor Display settings make the screen unreadable  Return to standard VGA settings; e.g., 640 x 480 By FITA AYALEW
  180. 180. Summary I/O (input/output) devices can be internal or external Basic input devices: keyboard, mouse, touch screens Specialty input: barcode readers, biometric devices Output devices: CRT monitor, LCD monitor, projector Video card: interfaces output device with PC system Port types: serial, parallel, USB, FireWire Serial and parallel ports are obsolescent technologies Current port technologies: USB 2.0 and FireWire All USB/FireWire devices are installed using PnP By FITA AYALEW
  181. 181. CHAPTER 10Multimedia Devices and Mass Storage By FITA AYALEW
  182. 182. Objectives Learn about multimedia devices such as sound cards, digital cameras, etc. Learn about optical storage technologies such as CD and DVD Learn how certain hardware devices are used for backups and fault tolerance Learn how to troubleshoot multimedia and mass storage devices By FITA AYALEW
  183. 183. Introduction • Multimedia capabilities of PCs:  Text, graphics, audio, video, animation Some applications for multimedia:  Videoconferencing for executives  Tools for teaching the alphabet to four-year-olds Mass storage devices hold multimedia data Types of mass storage  CDs, DVDs, removable drives, and tape drives By FITA AYALEW
  184. 184. Multimedia on a PC Goal: generate output that emulates reality Differences between cyberspace and real space  Sights and sounds in reality are continuous (analog)  Computer data is binary (discrete and digital) Challenge: bridge world of cyberspace with reality Topics covered:  CPU technologies used to process multimedia data  Multimedia devices; e.g., sound cards, MP3 players By FITA AYALEW
  185. 185. Sound Cards and Onboard Sound Operations performed on sound:  Basic: recording, storing, and replaying  Advanced: editing and mixing Types of ports  Output ports: used by speakers  Input ports: used by microphone, CD player, others Surround Sound: supports eight separate channels Sound Blaster card: standard for PC sound cards Use CD/DVD drive or TV tuner card to bypass CPU By FITA AYALEW
  186. 186. Figure 10-1 The Sound Blaster PCI 24-bit sound card hastwo internal connections and four ports By FITA AYALEW
  187. 187. Digital Cameras and Flash Memory Devices A digital camera works like a scanner  Scans the field of image set by the picture taker  Translates the light signals into digital values  Digital values can be stored, viewed, edited, printed TWAIN: format for transferring images to a PC  Connections may be cabled or wireless Solid state device (SSD): memory based on a chip  Examples: thumb drives and flash memory cards Flash memory cards are used in digital cameras By FITA AYALEW
  188. 188. Digital Cameras and Flash Memory Devices (continued) Transferring images to your PC  Install the software bundled with your camera  Connect your camera to the PC  Upload the images Editing or printing images once they are on the PC  Use image-editing software; e.g., Adobe Photoshop Picture file formats:  JPEG (Joint Photographic Experts Group) format  TIFF (Tagged Image File Format) Connect camera to TV using the video-out port By FITA AYALEW
  189. 189. Web Cameras and Microphones Web camera: captures digital video for use on Web Two meanings of Web cam:  Digital video camera  Web site providing live or prerecorded video broadcast Setting up a personal Web cam for a chat session  Use setup CD to install software  Plug in Web camera into a USB port  If sound is needed, plug in speakers and microphones  Use chat software to create a live video session By FITA AYALEW
  190. 190. Figure 10-2 Instant Messenger session using a Webcamera By FITA AYALEW
  191. 191. TV Tuner and Video Capture Cards TV tuner card: interfaces a PC with a TV Video capture card: saves video input to hard drive TV tuner/video capture card may also be a video card Three ways to incorporate tuner and capture features  Embed TV tuners and TV captures in motherboard  Fit card to fit into a PCI, PCI Express x16, or AGP slot  Connect external device to a USB port NTSC (National Television Standards Committee)  Sets standards for TV tuners and video capture cards By FITA AYALEW
  192. 192. Using CDs CD drives are read-only or read/writable CD surface  Continuous spiral of sectors of equal length  Data stored as lands (1) or pits (0) Process of reading data  Laser beam is passed over pits and lands on surface  Drive reads bit value by amount of laser deflection Process of writing data  CD imprinted (burned) with lands and pits Acrylic surface is added to protect the data By FITA AYALEW
  193. 193. Using CDs (continued) CD must read data at a constant rate Problem: linear velocity varies over rotating disk Solution 1: maintain constant linear velocity (CLV)  Slow down disk when laser is near center (200 rpm)  Speed up disk as laser goes to outer edge (500 rpm)  Rates given allow for transfer of 150 KBps (audio)  Drive speed must be increased for video Solution 2: maintain constant angular velocity (CAV)  Disk rotates at a constant speed  Technology is used in hard disks By FITA AYALEW
  194. 194. Using CDs (continued) Types of CD drives (also identifies disk)  CD-ROM drive: read only memory  CD-R drive: recordable CD  CD-RW: rewritable CD How an optical drive interfaces with motherboard  Using an ATA or SCSI interface  Using external drive that plugs into port, such as USB Installing a CD drive  Installed drive identified in directory by letter; e.g., D  Four choices for installation using parallel ATA (EIDE) By FITA AYALEW
  195. 195. Using DVDs DVD (digital video disc or digital versatile disc)  Single-sided holds up to 8.5 GB of data (movie length)  Double-sided disc can hold 17 GB of data  Uses the Universal Disk Format (UDF) file system Distinguishing between a CD and DVD  DVD can use top and bottom surfaces to hold data  Second opaque layer nearly doubles disc capacity Audio data stored in Surround Sound Video data stored using MPEG-2 video compression By FITA AYALEW
  196. 196. Using DVDs (continued) Various standards used for reading and writing Selection criteria for a DVD drive  The standards supported by the drive  Ability of drive to burn CDs  Write-once and rewritable speeds Latest DVD formats: HD-DVD and Blu-ray Installing a DVD drive  Follow the same procedure used for CD drives  Cabling: power cord, EDEI data cable, audio cord 4-pin connector for analog sound, 2-pin for digital sound By FITA AYALEW
  197. 197. Table 10-1 DVD standards By FITA AYALEW
  198. 198. Caring for Optical Drives and Discs Causes of problems:  Dust, fingerprints, scratches, defects, electrical noise  Drive is standing vertically Some precautions to follow:  Hold the disc by the edge  Use a soft, dry cloth to remove dust and fingerprints  Don’t paste paper on the surface of a CD  Don’t subject a disc to heat or leave it in direct sunlight  Don’t make the center hole larger  Don’t bend a disc By FITA AYALEW
  199. 199. Tape Drives Offer inexpensive, high capacity storage Advice: use backup software to manage backups Main disadvantage: data accessed sequentially  Makes file retrieval slow and inconvenient A tape drive can be internal or external How a tape drive interfaces with a computer  External or internal drive can use a SCSI bus  External or internal drive can use a USB connection  Internal drive can use parallel or serial ATA interface Some tips for cleaning and care  Keep tapes away from magnetic fields, heat, cold  Clean drive heads as recommended by manufacturer By FITA AYALEW
  200. 200. Problems with CD, CD-RW, DVD, or DVD-RWInstallation Check data cable and power cord connections For an EIDE drive, check master/slave jumper set Check for devices using the same port settings Run a virus scan programProblems when Burning a CD Make sure the disk capacity has not been exceeded Ensure hard drive has at least 1 GB of free space Close other programs before you begin Try a different brand of CDs Try using a slower burn rate By FITA AYALEW
  201. 201. Figure 10-3 Slow down the CD-RW write speed toaccount for a slow Windows system By FITA AYALEW
  202. 202. Troubleshooting Sound Problems Some questions to ask:  Are the speakers turned on?  Is the speaker volume turned up?  Is the volume control for Windows turned up? Some troubleshooting tasks for installation problems  Download new or updated drivers  Uninstall and reinstall the sound card Some ways to resolve issue of games without sounds  Update and install new drivers  Reduce sound acceleration By FITA AYALEW
  203. 203. Figure 10-4 Adjust sound hardware acceleration By FITA AYALEW
  204. 204. Summary Multimedia devices use digital data to model reality Sound cards enable you to record, store, replay, and edit sound Digital cameras work much like scanners Important image formats: JPEG and TIFF MPEG: set of compression standards for motion pictures, video, and audio Types of optical storage technology: CDs and DVDs CD/DVD disk surface uses lands and pits to represent binary data Other mass storage devices: tape drives, removable drives such as Zip By FITA AYALEW
  205. 205. CHAPTER 11Securing Your PC By FITA AYALEW
  206. 206. Objectives Learn how to secure a desktop or notebook computer Learn how malicious software works and how to clean an infected system Topics to cover  Methods for protecting computers and networks  How to use several security tools  How malicious software works  A step-by-step plan to remove malicious software By FITA AYALEW
  207. 207. Securing Your Desktop or Note book Computer •Reasons for providing additional security  Protection from attacks within the network  Attacks through security loopholes  Exposure during travel A few methods for securing a computer  Limit use of the administrator accounts  Keep Windows updates current  Physically protect your equipment  Keep good backups of user data  Destroy trash that might contain sensitive data By FITA AYALEW
  208. 208. Access Control Authentication: identifies an individual Authorization: assigns privileges/rights to individuals Types of passwords  Power-on passwords (configured in CMOS setup)  Windows passwords  Online account passwords  Application passwords Some rules for creating strong passwords  Combine upper/lower case letters, numbers, symbols  Do not use words in any language By FITA AYALEW
  209. 209. Access Control (continued) Controlling access to a PC using Windows  Set a user password for the user account  Configure user access to certain files and folders Overview for assigning permissions to file and folder  Disable simple file sharing from View in Folder Options  Open Properties window of a folder and select Sharing  Click Permissions and select options Protected files and folders display authentication box By FITA AYALEW
  210. 210. Limit Use of the Administrator Account Three common types of accounts in Windows  Administrator  Guest  Limited User Advice for protecting the Administrator Account  Create a Limited User account for ordinary activities  Use Administrator account for reserved activities  Change appearance of desktop to flag the account  Change strong password on a regular basis By FITA AYALEW
  211. 211. Use a Personal Firewall Firewalls are implemented in software or hardware Purpose of a firewall  Prevent worms or hackers from invading your system Turn on Windows Firewall to protect your system  It may be configured to allow for exceptions Windows Firewall is included with Service Pack 2 By FITA AYALEW
  212. 212. Use AV Software Antivirus (AV) software protects system from viruses Using AV software to greatest effect  Configure software to automatically download updates  Run AV software as a background process  Set software to automatically scan e-mail attachments Virus signature: distinguishing characteristics of virus AV software does not always stop adware or spyware Use removal program for adware or spyware  Example: Ad-Aware by Lavasoft ( By FITA AYALEW
  213. 213. Set Internet Explorer for Optimum Security •Some security features in Internet Explorer  Pop-up blocker  The ability to manage add-ons  he ability to block scripts  The ability to disable scripts embedded in Web pages  The ability to set the general security level Medium is recommended By FITA AYALEW
  214. 214. Figure 11-1 Control security settings for Internet Explorer By FITA AYALEW
  215. 215. Beware of Social Engineering Social engineering  Tricking people into giving out private information  Passing unsafe programs into the network or PC Some techniques of social engineers  Phishing: extracting personal data via e-mail  Scam e-mail: offers to join phony ventures  Virus (e-mail) hoax: clogs up e-mail systems A few rules for using the Internet  Do not click links inside e-mail messages  Investigate a Web site before downloading software By FITA AYALEW
  216. 216. Beware of Social Engineering (continued) Two ways to debunk a hoax e-mail  Note phrases/subjects that request mass forwarding  Use services of security site; e.g., Scripts: code segments automating set of tasks  Example: files with extensions .wsf and .vbs Malicious scripts are often hidden in e-mails  Example: the link Protecting against malicious scripts  Set Windows to display file extensions  Set Windows to first load script to Notepad By FITA AYALEW
  217. 217. Dealing with Malicious Software Malicious software (malware or computer infestation)  Any unwanted program intending harm to system  Transmitted to your computer without your knowledge Examples of malware: viruses and worms Some signs of malicious messages  Pop-up ads plague you when surfing the Web  Strange or bizarre error messages appear  Less memory than usual is available  Strange graphics appear on your computer monitor  The system cannot recognize the CD-ROM drive  Files constantly become corrupted  The OS boots, but cannot launch the Windows desktop  Your antivirus software displays one or more messages By FITA AYALEW
  218. 218. Heres the Nasty List Virus  Program that replicates by attaching to other programs  Infected program must execute for virus to run  Example: boot sector program  Protection: run AV software in the background Adware: produces all those unwanted pop-up ads Spam is junk e-mail that you do not want Spyware: program installing itself to spy on you Worm: self-replicating program that overloads network Browser hijacker: alters home page/browser settings Dialer: dials phone number without your knowledge Keylogger: tracks all your keystrokes Logic bomb: dormant code triggered by an event Trojan horse: disguises itself as a legitimate program By FITA AYALEW
  219. 219. Heres the Nasty List (continued) Types of viruses  Boot sector: virus hides in the boot sector program  File virus: hides in executable (.exe, .com, or .sys)  Multipartite virus: combined boot sector and file virus  Macro virus: hides in documents of macro files  Script virus: a virus that hides in a script How malware replicates and hides  Uses various techniques to load itself into memory  Attempts to hide from AV software  Example: stealth virus manipulates its storage file By FITA AYALEW
  220. 220. Step-by-Step Attack Plan Run reputable AV software  Examples: Norton Anti-Virus and McAfee VirusScan Run adware or spyware removal software  Example: Windows Defender by Microsoft Search out and destroy what’s left  Respond to any startup errors  Delete malicious files  Purge restore points  Clean the registry  Root out rootkits By FITA AYALEW
  221. 221. Security TipsBackup System Files Use Ntbackup to back up System State and registry When to back up the System State  After you have made major changes to the system  Example: after installing a new hard drive Make backups a routine part of monthly maintenancePerform a Monthly Security Maintenance Routine Change the administrator password Make sure system is being automatically updated Check that AV software is installed and current By FITA AYALEW
  222. 222. Summary Protect accounts and applications with passwords File and folders can be configured for selective permissions Standard security tools: AV software, firewalls, Windows Update Techniques used by social engineers: phishing, scam e- mails, virus hoaxes Some events to monitor: failed logon access attempts and network activity Malware: invasive programs such as viruses and worms If AV software cannot clean or delete malware, use other techniques such as deleting file from directory By FITA AYALEW
  223. 223. Wish You Good Luck