Causes of common problems

4.2 Given a scenario, troubleshoot common hardware failures.

📘CompTIA Server+ (SK0-005) 


Understanding why hardware fails is very important for the CompTIA Server+ exam. Hardware issues are mainly caused by technical factors (internal system problems) and environmental factors (external conditions like heat and dust). You must be able to identify, explain, and troubleshoot these causes.


1. Technical Causes

These are problems related to hardware components, configuration, or installation inside the server.


1.1 Power Supply Fault

What it is:

A failure in the Power Supply Unit (PSU) that provides power to all server components.

Causes:

  • Power surges or unstable electricity
  • Aging or worn-out PSU
  • Overloading (too many components drawing power)

Symptoms:

  • Server does not power on
  • Random shutdowns or restarts
  • Burning smell or unusual noise

Troubleshooting:

  • Check power cables and connections
  • Test with a known working PSU
  • Use a UPS to ensure stable power

1.2 Malfunctioning Fans

What it is:

Cooling fans inside the server are not working properly.

Causes:

  • Dust buildup
  • Fan motor failure
  • Loose or disconnected fan cables

Symptoms:

  • Increased internal temperature
  • Loud or unusual noises
  • System overheating warnings

Troubleshooting:

  • Inspect and clean fans
  • Replace faulty fans
  • Ensure proper airflow inside the chassis

1.3 Improperly Seated Heat Sink

What it is:

The heat sink is not correctly attached to the CPU or GPU.

Causes:

  • Loose mounting
  • Incorrect installation
  • Insufficient or dried thermal paste

Symptoms:

  • CPU overheating
  • Sudden shutdowns
  • Thermal warnings in BIOS or monitoring tools

Troubleshooting:

  • Reseat the heat sink properly
  • Apply thermal paste correctly
  • Ensure firm and even contact

1.4 Improperly Seated Cards

What it is:

Expansion cards (NIC, RAID controller, GPU) are not fully inserted into their slots.

Causes:

  • Movement during installation
  • Poor physical connection
  • Dust or obstruction in slots

Symptoms:

  • Device not detected
  • Intermittent connectivity issues
  • System errors related to hardware

Troubleshooting:

  • Power off and reseat cards
  • Check slot condition
  • Verify proper alignment and locking

1.5 Incompatibility of Components

What it is:

Hardware components that are not designed to work together.

Causes:

  • Unsupported RAM type or speed
  • Incorrect CPU for motherboard
  • Firmware or BIOS limitations

Symptoms:

  • System fails to boot
  • POST errors
  • Performance issues or instability

Troubleshooting:

  • Check compatibility lists (HCL – Hardware Compatibility List)
  • Update BIOS/firmware
  • Replace incompatible components

1.6 Cooling Failures

What it is:

The server fails to maintain safe operating temperature.

Causes:

  • Faulty fans or cooling systems
  • Poor airflow design
  • Blocked air vents

Symptoms:

  • High temperature alerts
  • System throttling (reduced performance)
  • Unexpected shutdowns

Troubleshooting:

  • Ensure proper airflow (front-to-back cooling)
  • Replace failed cooling components
  • Remove airflow obstructions

1.7 Backplane Failure

What it is:

Failure of the backplane, which connects drives to the system in rack servers.

Causes:

  • Electrical faults
  • Wear and tear
  • Connector damage

Symptoms:

  • Multiple drives not detected
  • RAID array failures
  • Disk connectivity issues

Troubleshooting:

  • Check backplane connections
  • Replace faulty backplane
  • Test drives individually

1.8 Firmware Incompatibility

What it is:

Mismatch between hardware and its firmware (BIOS, RAID controller firmware, etc.).

Causes:

  • Outdated firmware
  • Unsupported firmware versions
  • Improper updates

Symptoms:

  • Hardware not recognized
  • System instability
  • Boot failures

Troubleshooting:

  • Update firmware to compatible version
  • Follow vendor guidelines
  • Avoid unsupported combinations

1.9 CPU or GPU Overheating

What it is:

Processor or graphics unit generates excessive heat beyond safe limits.

Causes:

  • Cooling failure
  • Improper heat sink installation
  • High workload without proper cooling

Symptoms:

  • System throttling
  • Sudden shutdown
  • High temperature readings

Troubleshooting:

  • Improve cooling system
  • Clean dust from components
  • Monitor temperature using tools

2. Environmental Causes

These are external conditions that affect hardware performance and lifespan.


2.1 Dust

What it is:

Accumulation of dust inside the server.

Effects:

  • Blocks airflow
  • Causes overheating
  • Damages internal components

Symptoms:

  • High temperature
  • Fan noise
  • Reduced performance

Prevention / Troubleshooting:

  • Regular cleaning using compressed air
  • Use dust filters
  • Maintain clean server rooms

2.2 Humidity

What it is:

Excess moisture in the air.

Effects:

  • Corrosion of components
  • Short circuits
  • Electrical failures

Symptoms:

  • Random hardware failures
  • Rust or corrosion visible on parts

Prevention / Troubleshooting:

  • Maintain proper humidity levels (40–60%)
  • Use dehumidifiers
  • Monitor environment with sensors

2.3 Temperature

What it is:

Excessive heat or cold in the server environment.

Effects:

  • Overheating damages components
  • Cold environments can cause condensation

Symptoms:

  • System shutdowns
  • Reduced hardware lifespan
  • Performance degradation

Prevention / Troubleshooting:

  • Maintain optimal temperature (18–27°C)
  • Use proper cooling systems (HVAC)
  • Monitor temperature continuously

Key Exam Tips

  • Always separate technical vs environmental causes in questions.
  • Overheating is often linked to:
    • Fans
    • Heat sinks
    • Dust
    • Poor airflow
  • If multiple components fail, think:
    • Power supply
    • Backplane
  • If hardware not detected, think:
    • Improper seating
    • Firmware issues
    • Compatibility problems
  • Environmental issues often cause gradual degradation, not instant failure.

Summary

Hardware failures in servers are mainly caused by:

Technical Issues:

  • Power supply faults
  • Cooling and fan failures
  • Improper installation (heat sinks, cards)
  • Component incompatibility
  • Firmware issues
  • Backplane or overheating problems

Environmental Issues:

  • Dust
  • Humidity
  • Temperature

To pass the exam, focus on:

  • Recognizing symptoms
  • Identifying root causes
  • Applying correct troubleshooting steps
Buy Me a Coffee