5.1 - Troubleshooting Hardware

Definition: POST stands for Power On Self-Test.
Purpose: A self-test to determine if the core components of a computer system are installed and operational.
Checks include:
- CPU installed and able to communicate with BIOS hardware.
- Functionality of the video subsystem.
- Memory installation and operation.
Error Indications:
- If components fail, an error message will be displayed on-screen, and sound alerts (beeps) are emitted from the motherboard.
- Error messages and beep codes may vary by manufacturer.
- Reference documentation for manufacturer-specific beep codes rather than memorizing them.
- Importance of decoding: To identify which part of the BIOS failed and how to resolve the issue.

Blank screen with beeping noises suggests possible issues:
- Bad video on the motherboard
- Faulty memory or CPU.
BIOS Misconfiguration: Check BIOS configuration settings to ensure correct video subsystem settings.
CMOS Battery:
- A message indicating incorrect date and time suggests battery failure on the motherboard.
- Role: Maintains date and time when the computer is powered off.
- Solution: Replace the battery to resolve incorrect prompts at startup.

Booting from USB:
- Ensure correct boot order in BIOS settings.
- Internal SSDs should be prioritized over USB keys for booting.
- Valid operating system must be installed on bootable devices.
No media message indicates that BIOS will proceed to the next boot option if required devices are not connected.

Definition: Refers to a message displayed when the operating system cannot recover from a critical issue.
Sometimes referred to as the 'blue screen of death' (BSOD).
Implications:
- May require system restart.
- Work not saved may be lost unless steps were taken to prevent data loss.
Important BSOD details:
- Specific driver name or stop code present (e.g., Stop code: 0X Charlie 0000135).
- Further troubleshooting resources referenced online (e.g., www.windows.com/stopcode).
Possible Causes of BSOD:
- Bad hardware.
- Incorrect or outdated device drivers.
- Malicious or poorly designed applications.
Troubleshooting Steps:
- Utilize last known good configuration.
- Perform system restore to a prior date.
- Roll back recent driver installations.
- Attempt to boot in safe mode.
- Reseat adapter cards and memory modules to ensure good connections.
- Run hardware diagnostics provided by motherboard/hardware manufacturer and BIOS.

Applications may:
- Stop functioning suddenly.
- Provide error messages with vague details (e.g., "error 47829 (22573) frame buffer not supported").
Importance of documentation:
- Record error messages for technical support and troubleshooting.
- Take screenshots or photos of errors to provide context.
Proactive help desk strategies:
- Ask users to include screenshots in support tickets.

Check front drivers and connections:
- Is monitor connected? Verify all cables (HDMI, DisplayPort, USB-C) are properly connected.
- Check monitor power connections.
Monitor Settings: Ensure correct input selection is configured on the monitor.
Check brightness/contrast settings in monitor configuration if displays are faint.
Swap in a known good monitor to rule out hardware issues.

Communicate with multimeter for power checks:
- Check AC outlet functionality,
- Check power cord integrity,
- Verify power supply outputs for correct DC voltages.
Signs of power supply issues:
- Only fans working with no other components operating.
- Check connections and voltage outputs from the power supply.

Task Manager:
- Monitor % CPU, memory usage, disk activity, and network metrics for abnormal resource consumption.
- Performance tab provides graphical views to track resource usage over time.
System Maintenance:
- Ensure operating system updates are installed.
- Check disk space availability and consider disk defragmentation.
Laptops may throttle CPU during battery mode; connect to a power source for optimal performance.
Run antivirus/anti-malware scans to rule out malicious software affecting performance.

Internal Cooling Systems:
- Components that generate heat: CPUs, video adapters, memory.
- Cooling methods: fans, heatsinks, airflow management.
Fan Maintenance: Clean fans and ensure unobstructed airflow to maintain cooling efficiency.
Monitoring Tools:
- Utilize manufacturer or third-party software (e.g., HW Monitor) to check the status of internal sensors and temperatures.

Signs of failure:
- Visual evidence such as smoke or burning smell - remove power immediately.
- Identify damaged components visually; smell can guide you.
- Random shutdowns may indicate heat-related issues from insufficient cooling or failing hardware.
System logs: Check the Event Viewer to see if any logs were recorded before shutdowns.
Diagnostic Checks: Run a hardware diagnostic to rule out failing components.

Windows Event Viewer:
- Provides logs regarding application errors and system stability.
Reliability Monitor:
- Comprehensive history of application performance and failures.
- Helps correlate crashes with specific dates/times and offers various failure categories.
Reinstallation: Uninstall and reinstall problematic applications to ensure correct installation and resolve ongoing errors.
Continuous failures suggest underlying issues that require more in-depth analysis.

Unusual Noises:
- Grinding: potential hard drive failure.
- Rattling: loose components within the case.
- Clicking: obstructions in the fan's pathway.
- Popping/smoke: issues with capacitors on the motherboard – may indicate a need for hardware replacement.
Capacitor Inspection: Check for bulging tops or burnt components to identify failed hardware.

Significance of Battery: Maintains system date and time when disconnected from power.
Typical Battery Type: Flat button-style batteries easily replaceable. Check store availability.
Impact of Removal: Removing older batteries may reset BIOS configurations in older systems but typically does not in modern BIOS setups.
For full resets, use a jumper per the motherboard's instructions rather than solely battery removal.