L3: Troubleshooting Common Hardware Problems - CompTIA A+ 220-1101 - 5.2

Power-On Self-Test (POST)

• Definition: POST is a diagnostic testing sequence that occurs immediately on power-up to check key components of the PC.

• Components Checked:

  • CPU status

  • Video functionality

  • Keyboard operation

  • Memory (RAM) installation

• Error Indication:

  • If issues are detected, the system emits beep codes or displays error messages.

  • Different beep patterns correspond to different errors, highlighting hardware issues.

  • Important to refer to the motherboard's documentation for beep code meanings.

BIOS and System Errors

• BIOS Role: The Basic Input/Output System is responsible for tracking system date and time.

• Battery Dependency: A battery on the motherboard keeps time; failure results in recurring manual resets.

• Boot Order Issues:

  • Incorrect boot drive may lead to startup failures.

  • Check BIOS boot order settings to prioritize correct drives.

  • USB drives may sometimes attempt to boot first; unplugging can resolve the issue.

• Windows Stop Error (Blue Screen of Death):

  • Indicates a critical failure; requires system restart to recover.

  • Can view details in Windows Event Viewer post-restart for troubleshooting insights.

  • Visit the Microsoft website for stop code references and further support.

  • Typical causes include faulty hardware, incompatible drivers, or system application errors.

  • Recovery methods: Last Known Good Configuration, Safe Mode boot, system restore.

    

System Performance Issues

• Slow Performance: Possible causes include:

  • Background processes like Windows Update.

  • Low disk space affecting system operations.

  • Laptop power settings may throttle CPU to save battery.

• Monitoring Tools: Use Task Manager to view CPU usage; identify resource-heavy applications or processes.

• Heat Management: High temperatures can cause throttling; ensure proper fan and ventilation function.

• Dust Accumulation: Clean PC components to improve airflow and cooling efficiency.

Troubleshooting Tips

• Black Screen Issues:

  • Verify monitor power connections and input source settings.

  • Check for any output via alternate inputs like HDMI, DisplayPort, etc.

  • Replace the monitor temporarily to identify possible hardware failure.

• Power Issues:

  • If the system fails to power on, inspect power cables and connections.

  • Use multimeter to check power supply functionality.

  • Validate whether power is reaching motherboard and components through checks.

    

• Unusual Noises:

  • Grinding noises indicate possible hardware failure; remove or secure components as needed.

  • Clicking sounds may signal drive or fan issues; inspect for obstructions.

System Freezes

• Unresponsive System:

  • Check for activity lights; ensure the mouse locks or status indicators are operational.

  • Recent changes (hardware/drivers) may be the cause.

  • If completely stuck, perform hardware diagnostics.

Repeated Restarts

• Troubleshooting Cycles: Track where reboot occurs (BIOS, OS startup).

• Configuration Recovery: Use the F8 key for Last Known Good Configuration, especially after driver updates.

• Safe Mode: Booting in Safe Mode loads minimal drivers, useful for isolating issues.

Additional Diagnostics

• Capsule Failure: Monitor the health of capacitors on the motherboard; bulging or leaking caps require replacement.

• Event Viewer and Reliability Monitor: Analyze logs for errors that might indicate hardware or software failures.

• BIOS Battery Issues: Discharged batteries may reset time/date; replacement accessible and vital for stable operation.

• Resetting BIOS: For a full BIOS reset, short the jumper rather than just removing the battery.