IHW H5

• Disassembly Overview


  1. It is seldom necessary to completely disassemble a computer

  2. Disassembly can be informative and fun for a technician learning about PCs

  3. Disassembly may be done to perform preventive cleaning or troubleshoot a problem

  4. Disassembly outside the case may help diagnose grounding problems

  5. Remove jewelry and use proper lifting techniques before disassembling
• Electrostatic Discharge (ESD)


  • A difference of potential between two items that cause static electricity
  • Can damage electronic equipment without the technician's knowledge
  • The average person requires 3,000 volts to feel it, but electronic components can be damaged with as little as 30 volts
  • Effects of static electricity can be cumulative, weakening or eventually destroying a component
  • ESD event is not recoverable
• Electronic chips and memory modules


  • Most susceptible to ESD strikes
• Atmospheric conditions affect static electricity
• Antistatic wrist strap


  • Also called an ESD strap
  • One end encircles the technician's wrist, the other end attaches to a grounding post or metal part
  • Allows the technician and the computer to be at the same voltage potential, preventing static electricity
• Technicians should not wear an ESD wrist strap when working inside a CRT monitor or power supply due to high voltages
• Antistatic gloves


  Can be used instead of an antistatic wrist strap, especially for laptops that lack good places to attach a wrist strap
• Antistatic bags, ESD mats, antistatic heel straps

  • Used to store spare parts and reduce ESD risk
• Self-grounding method


  Placing bare arm on power supply to keep technician and computer at same voltage potential, reducing ESD risk
• Electronics manufacturers are designing components less susceptible to ESD, but each zap still weakens a component
• Electromagnetic Interference (EMI)


  • Noise caused by electrical devices
  • Can negatively affect computers through radio frequency interference (RFI)
• EMI/RFI can affect any electronic circuit, including files on a hard drive
• Basic tools a technician should not go on a repair call without

  • Small and medium flat-tipped screwdrivers
  • #0, #1, and #2 Phillips screwdrivers
  • 1/4- and 3/16-inch hex nut drivers
  • Small diagonal cutters
  • Needle-nose pliers
• Magnetic screwdrivers


  Handy for picking up dropped screws, but can affect memory so should be avoided if possible
• Tools that are nice to have but not used daily

  • Screw pick-up tool
  • Screwdriver extension tool
  • Soldering iron, solder, and flux
  • Screw-starter tool
  • Medium-size diagonal cutters
  • Metric nut drivers
  • Cable-making tools
  • Cable tester
  • Loopback plug
  • Punch-down tool
  • Toner generator and probe
  • Wire/cable stripper
  • Crimper
  • WiFi analyzer
  • External enclosure
  • AC circuit tester
  • Right-angled, flat-tipped, and Phillips screwdrivers
  • Hemostats
  • Pliers
  • Optical laser cleaning kit
  • Nonstatic low-airflow vacuum or toner vacuum
  • Compressed air
  • Disposable gloves
  • Safety goggles
  • Air filter/mask
  • Small plastic scribe
  • T8, 10, 15, 20, and 25 Torx (star) screwdriver
• Disassembly Steps


  1. Do not remove the motherboard battery

  2. Use proper grounding procedures to prevent ESD damage

  3. Keep paper, pen, phone, and camera nearby for note taking, diagramming, and photo taking

  4. Have ample flat and clean workspace

  5. When removing adapters, do not stack them on top of one another

  6. Place removed adapters in ESD protective bags

  7. Handle adapters, motherboards, and processors on the side edges, avoid touching gold contacts

  8. Handle hard drives carefully to avoid data damage

  9. Can remove power supply but do not disassemble CRT monitor or power supply without proper training and tools

  10. Document screw and cable locations, label if possible
• Disassembly Steps: Remove Power and External Cables

  Remove power cord

  Remove external cables, make notes on which cable attaches to each port
• Disassembly Steps: Open the Case


  Some cases have tabs, covers, or retention levers that must be pressed to open

  Make diagrams and place screws in labeled sections of an egg carton as they are removed
• Disassembly Steps: Remove Internal Cables and Connectors

  Internal cables commonly connect devices to motherboard, power supply to devices, motherboard to front panel
• Removing computer case


  1. Press tabs on top and bottom of computer

  2. Pry open cover

  3. Some cases have screws that loosen but don't need to be fully removed
• Place screws in an egg carton with each section labeled for where they came from
• To remove or loosen a screw, turn the screwdriver to the left
• Refer to manufacturer's directions when opening a case
• Most of the time, you can access the inside of the computer by simply removing the screws that hold down the side panel
• Removing internal cables and connectors


  1. Identify cable orientation and keying

  2. Use pull tabs or plastic pieces to remove cables

  3. Release locking tabs before disconnecting cables

  4. Be careful with drive cables
• Pin 1


  The cable edge that is colored, identifies the orientation of the cable
• Ensure cables are connected tightly, evenly, and securely
• Motherboard connectors are usually notched so the cable inserts only one way
• Refer to motherboard documentation for proper cable orientation
• Front panel cables must be connected to the appropriate motherboard pins in the correct direction
• Fans can connect to 3-pin or 4-pin motherboard connectors
• Removing adapters


  1. Observe ESD avoidance

  2. Use edges to pull adapter upward out of expansion slot

  3. Do not touch gold contacts

  4. Insert blank cover in empty expansion slot
• Removing storage devices


  1. Handle hard drives carefully to avoid damage

  2. Solid-state drives are susceptible to ESD

  3. Secure drives using screws or rails
• Removing motherboard


  1. Remove I/O shield

  2. Leave plastic/metal standoffs attached

  3. Press down, lift up, or bend retaining clips to slide motherboard out
• All-in-one computers have components installed on the back of the display
• Reassembling a computer


  1. Reinsert all components in proper places

  2. Ensure motherboard is securely seated

  3. Reconnect cables and connectors properly
• Dust accumulation inside a computer can cause overheating and component failure
• Preventive maintenance


  1. Clean computer at least once a year

  2. Vacuum computer and clean optical drive, keyboard, printer, display

  3. Ensure proper ventilation
• Use wipes or a soft lint-free cloth dampened with water or isopropyl alcohol to clean LCD monitors and laptop displays
• Always ensure that the device has proper ventilation and that vents are clear of any obstructions