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Computer Hardware Safety

Computer Hardware Safety

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Computer Hardware Safety

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  1. Computer Hardware Safety PC Repair Fundamentals

  2. 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 what happens when you first turn on a PC before the OS is loaded

  3. Objectives (continued) • Learn how to approach and solve a PC problem • Learn how to troubleshoot a failed boot before the OS is loaded

  4. Introduction • Basic repair skills • Developing a maintenance plan • Implementing a maintenance plan • Working inside a computer case • Following sequence of events that occur at startup • Advanced repair skills • Using common-sense guidelines to solve problems • Interviewing a user • Determining if a problem occurs before or after boot • Troubleshooting and solving a problem of a failed boot

  5. 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

  6. Figure 2-1 PC support technician tools

  7. 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

  8. Figure 2-2 Windows Setup CD and Windows Recovery CDs for a notebook computer

  9. 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

  10. Figure 2-3 Loop-back plugs used to test serial and parallel ports

  11. 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)

  12. Figure 2-5 Each chemical you use should have available a material safety data sheet

  13. 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.

  14. Figure 2-6 Post Code Master diagnostic card by MSD, Inc.

  15. 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

  16. 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

  17. Figure 2-9 Configure antivirus software to scan e-mail and instant message attachments and to download updates automatically

  18. 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

  19. 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

  20. Preparing a Computer for Shipping • Adverse factors to consider: • Rough handling • Exposure to water, heat, and cold • Misplacement or theft of computer • Some shipping guidelines to follow: • Backup the hard drive onto a backup medium • Remove inserted disks, tape cartridges, or CDs • Coil and secure all external cords • Separately wrap hardware components • Purchase insurance on the shipment

  21. Disposing of Used Equipment • Various guidelines for disposing of equipment: • Table 2-2 • Manufacturer documentation • Local environmental regulators • Danger posed by monitors and power supplies • Residual charge in capacitors can cause shock • Modern devices discharge if unplugged for 60 minutes • Older devices may require discharge with a probe • Destroy secondary storage devices with sensitive data

  22. Table 2-2 Computer parts and how to dispose of them

  23. 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

  24. 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 • If working inside a monitor, do not ground yourself

  25. Figure 2-13 A ground bracelet, which protects computer components from ESD, can clip to the side of the computer case and eliminate ESD between you and the case

  26. 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

  27. Figure 2-19 Removing the cover

  28. 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)

  29. Figure 2-33 Remove the motherboard from the case

  30. Steps to Put a Computer Back Together • 1. Install power supply, drives, motherboard, cards • 2. Connect all data and power cables • 3. Plug in the keyboard, monitor, and mouse • 4. Ask instructor to check work (if in a classroom) • 5. Turn on the power and check PC functions

  31. Understanding the Boot Process • Key learning objectives • Know how to boot a PC • Understand what happens first when a PC is turned on • Understand how an operating system is loaded

  32. Booting a Computer • Process that drives a computer to a working state • Hard (cold) boot: turn the power switch on • Soft (warm) boot: allow the OS to reboot • How to soft boot Windows XP • Click Start • Click Turn Off Computer • Click Restart

  33. Choosing Between a Hard Boot and a Soft Boot • Hard boots are more stressful on machines • Power surges through system when PC is turned on • Reasons to choose a soft boot over hard boot • Less stressful on the machine • Faster due to skipping initial steps • Some computers have a soft and hard power switch • Soft power switch shuts down and restarts Windows • Hard power switch cuts power and restarts machine

  34. The Startup BIOS Controls the Beginning of the Boot • The startup BIOS gets a system up and running • Four phases of the boot process: • BIOS runs the POST and assigns system resources • POST: power-on self test • BIOS searches for and loads an OS • OS configures system and completes its own loading • Application software is loaded and executed

  35. Figure 2-40 Boot Step 1: The ROM BIOS startup program surveys hardware resources and needs and assigns system resources to satisfy those needs

  36. Changing the Boot Sequence • BIOS looks to CMOS RAM to locate the OS • Boot sequence: order of drives checked for an OS • Change boot sequence using CMOS setup utilities • Access CMOS setup utilities when PC is turned on • Example: press F8 before Windows screen appears

  37. Figure 2-42 Numbered steps show how BIOS searches for and begins to load an operating system (in this example, Windows NT/2000/XP is the OS)

  38. How to Troubleshoot a PC Problem • Assume the attitude of an investigator • Do not compound the problem by your own actions • Look at the problem as a learning opportunity • Ask questions until you understand the problem • Believe that you can solve the problem

  39. Steps to Solving a PC Problem • Key advice: • Ask good questions • Document the process • Four-step problem solving process: • Step 1: Interview the user • Step 2: Back up data • Step 3: Solve the problem • Step 4: Verify the fix and document the solution

  40. Figure 2-44 General approach to troubleshooting

  41. Troubleshooting a Failed Boot • It takes time to acquire troubleshooting skills • Hands-on training: troubleshooting a failed boot

  42. My Computer Won’t Boot • First step: maintain your calm • Second step: develop a game plan • Figure 2-45 provides a procedure • Plan is driven by a set of yes-no questions • Example: Does the PC boot properly? • If no, troubleshooter is directed to another question • If yes, troubleshooter is directed to stop (for now)

  43. Figure 2-45 Use this flowchart when first facing a computer problem

  44. Troubleshooting Major Subsystems Used For Booting • Categories of troubleshooting steps in Figure 2-45 • The electrical subsystem • Essential hardware devices • The motherboard, memory, and the CPU • Video • Reading from the hard drive • Key aides: tables identifying error codes

  45. Table 2-4 Beep codes and their meanings

  46. 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

  47. Summary (continued) • Assembling and reassembling a PC prepares the technician for actual repair work • Startup BIOS controls when the boot process begins • Four step boot process: POST, loading the OS, OS initializing itself, loading and executing applications • Expert troubleshooters ask good questions • Before tackling a problem, develop a game plan