Diagnosing Hardware Problems
Estimated Lesson Time: 50–60 Minutes
Lesson Overview
Microsoft Flight Simulator is one of the most demanding consumer applications available.
Unlike many games that heavily stress only the graphics card, Flight Simulator places sustained workloads on almost every major component in your PC, including:
- CPU
- GPU
- RAM
- VRAM
- Storage
- Cooling system
- Power delivery
This makes it an excellent stress test—but it also means hardware issues often appear here before they appear anywhere else.
A system may perform perfectly in short benchmarks or less demanding games yet become unstable after a long flight because of heat, power limits, memory errors or storage problems.
This lesson will teach you how to recognise the warning signs of hardware problems, interpret monitoring data correctly and determine whether your PC is operating within its normal range.
The goal is not to memorise ideal temperatures or utilisation figures. The goal is to understand how healthy hardware behaves and how to identify abnormal behaviour before replacing components or making unnecessary changes.
Lesson Objectives
By the end of this lesson you will understand:
How to recognise CPU overheating.
How to recognise GPU overheating.
What thermal throttling is.
RAM instability.
VRAM limitations.
SSD health.
PSU-related problems.
Power limits.
Hardware monitoring.
Event Viewer.
HWiNFO diagnostics.
How to determine whether hardware is operating normally.
1. Why Hardware Diagnostics Matter
Many users assume poor performance automatically means they need:
- A faster graphics card.
- More RAM.
- A better CPU.
In reality, perfectly capable hardware can perform badly if something is preventing it from operating correctly.
Examples include:
- Dust blocking airflow.
- A CPU cooler mounted incorrectly.
- A GPU reaching thermal limits.
- Unstable memory settings.
- An SSD nearing failure.
- A power supply unable to deliver stable power.
- Incorrect BIOS settings.
Professional optimisation begins by confirming the hardware is healthy before changing software.
2. Understanding Normal Hardware Behaviour
Every component has an expected operating range.
During a demanding MSFS flight it is normal to see:
- High CPU utilisation on one or more cores.
- High GPU utilisation if GPU limited.
- Increased RAM usage.
- Rising VRAM usage.
- Increased temperatures.
- Higher fan speeds.
- Increased power draw.
These are not problems by themselves.
The objective is to identify behaviour that falls outside what is expected.
3. CPU Overheating
The CPU performs:
- Flight model calculations.
- Aircraft systems.
- AI traffic.
- Terrain loading.
- Glass cockpit updates.
- Object placement.
As workload increases, temperature rises.
Modern CPUs are designed to run warm under load, but excessive temperatures can reduce performance.
Symptoms
- FPS gradually decreases.
- MainThread becomes worse over time.
- CPU clock speeds begin to fall.
- Fans remain at maximum.
- Performance improves after cooling down.
What Causes CPU Overheating?
- Dust build-up.
- Poor airflow.
- Incorrect cooler installation.
- Dry thermal paste.
- Small PC case.
- Aggressive overclock.
- High room temperature.
Monitoring
Use:
- HWiNFO
- MSI Afterburner
- Ryzen Master (AMD)
- Intel XTU (Intel, where appropriate)
Record:
- CPU package temperature.
- Clock speed.
- Power draw.
4. GPU Overheating
The GPU renders:
- Clouds.
- Shadows.
- Terrain.
- Textures.
- Water.
- Reflections.
- Anti-aliasing.
High utilisation naturally increases GPU temperature.
Symptoms
- FPS falls gradually.
- GPU clock speeds reduce.
- Fans increase dramatically.
- GPU utilisation fluctuates unexpectedly.
- Driver instability develops.
Common Causes
- Dust.
- Poor airflow.
- Overclock instability.
- High ambient temperature.
- Blocked fans.
Monitor
Record:
- GPU temperature.
- Hotspot temperature (if available).
- Clock speed.
- Fan speed.
- Power draw.
5. Thermal Throttling
Thermal throttling is a protective mechanism.
When a component becomes too hot, it deliberately reduces its own performance to lower temperature.
Instead of shutting down immediately, it slows itself.
This protects the hardware from damage.
Signs
- Temperatures remain very high.
- Clock speeds suddenly reduce.
- FPS decreases.
- Utilisation falls unexpectedly.
CPU Example
Normal:
5.0 GHz
↓
Temperature increases
↓
Clock reduces to 4.2 GHz
↓
Performance decreases
GPU Example
Normal:
2,700 MHz
↓
Temperature increases
↓
Clock reduces to 2,300 MHz
↓
FPS falls.
6. RAM Instability
RAM stores:
- Aircraft systems.
- Scenery.
- Simulator data.
- Navigation databases.
- Temporary files.
Unlike RAM capacity, RAM stability concerns whether data is stored and retrieved correctly.
Causes
- Unstable EXPO/XMP.
- Mixed memory kits.
- Faulty memory.
- Manual timing changes.
- Memory-controller instability.
Symptoms
- Random CTDs.
- Application crashes.
- Blue screens.
- Corrupted downloads.
- Simulator instability.
Important
High RAM usage is not the same as unstable RAM.
A system can use 90% of available RAM perfectly safely if it remains stable.
7. VRAM Limitations
VRAM stores:
- Textures.
- Geometry.
- Frame buffers.
- Shadow maps.
- Terrain.
When VRAM becomes exhausted:
The GPU begins moving data between VRAM and system RAM.
This process is significantly slower.
Symptoms
- Texture pop-in.
- Heavy stutters.
- FPS drops.
- Long pauses.
- Delayed scenery loading.
Monitor
Use:
MSI Afterburner
HWiNFO
NVIDIA App
AMD Adrenalin
Record:
- VRAM allocated.
- VRAM used.
- GPU utilisation.
8. SSD Health
The simulator continuously reads:
- Scenery.
- Aircraft.
- Textures.
- World data.
A failing SSD can produce:
- Long loading.
- Freezes.
- Missing files.
- Corrupted packages.
Monitor
Check:
- SMART status.
- Health percentage.
- Remaining life.
- Temperature.
- Read errors.
Tools include:
- CrystalDiskInfo
- Manufacturer utilities
- HWiNFO
Signs of SSD Problems
- Loading becomes progressively slower.
- File corruption.
- Windows disk warnings.
- Read/write errors.
9. PSU Issues
The Power Supply Unit provides stable electrical power.
If the PSU cannot deliver sufficient or stable power, symptoms may include:
- Sudden shutdowns.
- Random restarts.
- GPU driver crashes.
- Black screens.
- Complete power loss.
Unlike overheating, PSU failures often occur without warning.
Common Causes
- Age.
- Poor-quality PSU.
- Insufficient wattage.
- Loose power cables.
- Faulty connectors.
Important
A PSU issue cannot usually be diagnosed by software alone.
Instead, look for patterns:
- Only under heavy load.
- Complete shutdowns.
- Other demanding games behaving similarly.
10. Power Limits
Modern CPUs and GPUs have configurable power limits.
These determine how much electrical power a component may consume.
Examples:
AMD Precision Boost.
Intel Turbo Boost.
GPU power targets.
If power limits are too restrictive:
Clock speeds reduce.
Performance decreases.
Temperatures remain lower than expected.
11. Hardware Monitoring
Monitoring software provides evidence.
Never diagnose based on feeling.
Recommended tools:
- HWiNFO
- MSI Afterburner
- NVIDIA App
- AMD Adrenalin
- Task Manager
- Resource Monitor
Monitor:
- CPU clocks.
- GPU clocks.
- Temperatures.
- Utilisation.
- Power draw.
- RAM.
- VRAM.
- Disk activity.
12. Event Viewer
If hardware becomes unstable, Windows may record:
- Driver failures.
- Hardware errors.
- WHEA errors.
- Unexpected shutdowns.
- Application crashes.
Review:
Windows Logs
↓
System
↓
Application
Look for repeated events occurring at the same time as benchmark failures.
13. HWiNFO Diagnostics
HWiNFO is one of the most powerful hardware-monitoring tools available.
It provides:
- Temperatures.
- Voltages.
- Power.
- Clock speeds.
- Memory usage.
- Storage temperatures.
- Fan speeds.
- CPU package power.
- GPU hotspot.
Rather than focusing on one value, observe how these values change throughout an entire flight.
Professional Diagnostic Workflow
Step 1
Run your permanent benchmark.
Step 2
Monitor:
- CPU temperature.
- GPU temperature.
- CPU clocks.
- GPU clocks.
- RAM.
- VRAM.
- SSD temperature.
- Power draw.
Step 3
Observe whether values remain stable.
Step 4
Look for abnormalities.
Examples:
Clock reductions.
Temperature spikes.
Unexpected utilisation drops.
Step 5
Review Event Viewer if instability occurred.
Step 6
Document all findings.
Worked Example
Problem
Performance drops after 90 minutes.
Data
CPU temperature:
87°C
GPU:
66°C
CPU clocks:
5.0 GHz
↓
4.3 GHz
GPU clocks:
Stable.
Analysis
GPU remains stable.
CPU clock decreases.
Temperature continues rising.
Likely thermal throttling.
Conclusion
The simulator itself is functioning correctly.
Cooling should be investigated before changing graphics settings.
Another Example
Problem
Random CTDs.
Data
Temperatures:
Normal.
Clock speeds:
Normal.
RAM:
EXPO enabled.
Windows Event Viewer:
WHEA memory errors.
Analysis
Hardware instability is suspected.
Testing at stock memory settings confirms stability.
Conclusion
The issue was unstable memory rather than Microsoft Flight Simulator.
Common Mistakes
Assuming high temperatures automatically mean a fault.
Replacing hardware without monitoring it.
Ignoring clock speeds.
Confusing RAM usage with RAM instability.
Assuming every crash is caused by MSFS.
Ignoring SSD health.
Monitoring only the GPU.
Student Task
Hardware Health Benchmark
Run your permanent benchmark flight while monitoring your hardware.
Record:
CPU
- Temperature.
- Average clock speed.
- Peak clock speed.
- Power draw.
- Utilisation.
GPU
- Temperature.
- Hotspot temperature.
- Clock speed.
- Utilisation.
- Power draw.
- VRAM usage.
Memory
- RAM usage.
- VRAM usage.
Storage
- SSD temperature.
- SSD health.
- Free storage.
Windows
Review Event Viewer.
Record any warnings or errors that occurred during the benchmark.
Analysis
Determine whether any hardware component operated outside its expected range.
If abnormalities were detected:
- Form a hypothesis.
- Explain the evidence.
- Suggest one controlled test to investigate further.
- Repeat the benchmark after that single change.
Hardware Diagnostic Report
System Information
CPU:
GPU:
RAM:
Storage:
PSU:
CPU
Temperature:
Average Clock:
Peak Clock:
Power:
Utilisation:
GPU
Temperature:
Hotspot:
Clock:
Power:
VRAM:
Utilisation:
Storage
Health:
Temperature:
Free Space:
Windows Diagnostics
Event Viewer Findings:
Reliability Monitor Findings:
Overall Assessment
Is the hardware operating normally?
Yes / No
If no:
Which component?
Evidence:
Recommended next step:
Student Checklist
CPU monitored.
GPU monitored.
Clock speeds recorded.
Temperatures recorded.
RAM and VRAM monitored.
SSD health checked.
Power behaviour reviewed.
Event Viewer checked if instability occurred.
HWiNFO logs reviewed.
Final hardware assessment completed.
Lesson Summary
Congratulations.
You now understand how to diagnose hardware problems using evidence rather than assumptions.
Remember:
- Microsoft Flight Simulator places sustained stress on every major component in a modern gaming PC.
- High utilisation and warm temperatures are often normal under load, but overheating, falling clock speeds and instability are not.
- Thermal throttling occurs when hardware deliberately reduces performance to protect itself.
- RAM instability is different from high RAM usage, and VRAM exhaustion can cause severe stuttering even when the GPU is powerful.
- SSD health and available storage influence loading behaviour and overall responsiveness.
- Power supply issues often appear as sudden shutdowns or restarts under heavy load rather than simple FPS loss.
- Monitoring tools such as HWiNFO, MSI Afterburner and Event Viewer provide the evidence needed to diagnose hardware accurately.
- Always investigate hardware methodically before assuming the simulator or graphics settings are responsible.
Knowledge Check
- What is the difference between normal high temperatures and thermal throttling?
- How can falling clock speeds indicate a cooling problem?
- Why is RAM instability different from high RAM usage?
- What symptoms might suggest VRAM has been exhausted?
- How can SSD health affect Microsoft Flight Simulator?
- What symptoms are commonly associated with PSU-related problems?
- Why should Event Viewer be checked after hardware instability?
- What information can HWiNFO provide that is useful during a benchmark?
- Why should hardware be monitored over an entire flight rather than for only a few minutes?
- Based on your benchmark data, did any component operate outside its expected range, and what evidence supports your conclusion?