5.1 Given a scenario, troubleshoot motherboards, RAM, CPUs, and power.
📘CompTIA A+ Core 1 (220-1201)
When a computer doesn’t work properly, there are usually visible signs or behaviors that indicate which component is failing. Recognizing these symptoms is a key skill for the exam. Here’s a detailed breakdown:
1. Power-On Self-Test (POST) Beeps
- What it is: When you turn on a PC, the motherboard runs POST to check that hardware is working. If something is wrong, the motherboard emits a series of beeps.
- Why it happens: Each beep pattern corresponds to a hardware issue (like RAM failure, video card issues, or CPU problems). The exact beep codes depend on the BIOS manufacturer (AMI, Phoenix, Award).
- Exam tip: Know that POST beeps indicate hardware failure before the system boots. For example:
- 1 long beep + 2 short beeps → video card issue.
- Continuous beeps → RAM or motherboard problem.
2. Proprietary Crash Screens
- What it is: Some operating systems (especially Windows) show a specific “blue screen” or other crash screens when the system fails critically.
- Why it happens: A crash screen often indicates a software issue interacting with hardware, like faulty RAM or a CPU overheating.
- Exam tip: These screens give clues about which component is failing—check error codes.
3. Blank Screen
- What it is: The monitor stays black when the computer is turned on.
- Why it happens: Common causes include:
- No power to the video card or monitor.
- CPU or RAM failure.
- Motherboard not initializing.
- Exam tip: Start by checking connections and ensuring the monitor and video card are working.
4. No Power
- What it is: The PC does not turn on at all—no lights, no fans.
- Why it happens: Could be due to:
- Failed power supply unit (PSU).
- Dead motherboard.
- Faulty power button or wiring.
- Exam tip: Always check the PSU first and test with another power outlet.
5. Sluggish Performance
- What it is: The system runs slowly or freezes.
- Why it happens: Possible causes:
- Low RAM or failing memory modules.
- CPU underperforming or overheating.
- Software overload.
- Exam tip: Sluggishness often indicates resource problems (CPU/RAM) rather than total hardware failure.
6. Overheating
- What it is: System shuts down or shows thermal warnings.
- Why it happens: CPU or GPU running too hot due to:
- Failed cooling fans.
- Dust buildup.
- Thermal paste degraded.
- Exam tip: Overheating can damage CPUs or motherboards, so cooling solutions must be checked.
7. Burning Smell
- What it is: Smell of electronics burning.
- Why it happens: Usually caused by:
- Electrical short circuits.
- Failing PSU or motherboard.
- Overloaded components.
- Exam tip: A burning smell requires immediate power-off and inspection—this is critical to prevent further damage.
8. Random Shutdown
- What it is: System turns off unexpectedly.
- Why it happens: Could be:
- Overheating CPU or GPU.
- Power supply instability.
- Faulty motherboard.
- Exam tip: Look for patterns, like shutdown after high load, which points to thermal or power issues.
9. Application Crashes
- What it is: Programs close unexpectedly or fail to start.
- Why it happens: Common causes include:
- Failing RAM or storage.
- Corrupt system files.
- CPU errors.
- Exam tip: Repeated crashes often indicate hardware instability, even if the OS is running.
10. Unusual Noise
- What it is: Clicking, buzzing, or whirring from the PC.
- Why it happens: Often caused by:
- Failing hard drives.
- Faulty fans.
- Electrical issues on motherboard.
- Exam tip: Noise can signal mechanical failure or PSU/motherboard electrical problems.
11. Capacitor Swelling
- What it is: Physical bulging or leaking on the motherboard capacitors.
- Why it happens: Capacitors wear out or fail due to age, heat, or power surges.
- Exam tip: Swollen capacitors are a clear sign the motherboard must be replaced.
12. Inaccurate System Date/Time
- What it is: The clock resets or shows wrong time after shutdown.
- Why it happens: Usually caused by:
- Dead CMOS battery on the motherboard.
- Exam tip: Replacing the CMOS battery is an easy fix for date/time issues.
✅ Summary for Exam
- POST beeps, crash screens, blank screens, no power → immediate hardware check.
- Sluggish performance, application crashes → RAM or CPU issues.
- Overheating, random shutdown, burning smell → thermal or power issues.
- Unusual noises, capacitor swelling → hardware failure.
- Incorrect date/time → CMOS battery issue.
Remember: On the exam, you may be given a symptom and asked which component is most likely at fault. Linking symptoms to specific hardware is key.
