GPU Monitoring & Performance Analysis
Estimated Lesson Time: 40–50 Minutes
Lesson Overview
Throughout this course, we’ve discussed CPU bottlenecks, GPU bottlenecks, graphics settings and driver optimisation.
However, none of that knowledge is useful unless you know how to measure what’s actually happening inside your PC.
Professional optimisation isn’t based on guessing.
It’s based on data.
In this lesson, you’ll learn how to monitor your graphics card in real time and interpret the information correctly.
Rather than simply watching FPS, you’ll learn how to analyse:
- GPU utilisation.
- VRAM usage.
- GPU clock speeds.
- GPU temperatures.
- GPU power draw.
- Frame consistency.
By the end of this lesson, you’ll be able to understand what your graphics card is doing throughout an entire flight and identify whether it’s operating efficiently.
Lesson Objectives
By the end of this lesson you will understand:
GPU utilisation.
VRAM usage.
GPU clock speeds.
GPU temperatures.
GPU power draw.
MSI Afterburner.
HWiNFO.
NVIDIA App Performance Overlay.
How to analyse a complete flight.
Why Monitoring Matters
One of the biggest mistakes Flight Simulator users make is assuming performance problems without measuring anything.
For example:
“My simulator is stuttering.”
That could be caused by:
- CPU limitation.
- GPU limitation.
- VRAM limitation.
- Thermal throttling.
- Background applications.
- Streaming scenery.
- Add-ons.
- Driver issues.
Without monitoring software, you’re simply guessing.
Good optimisation always begins with accurate measurements.
1. GPU Utilisation
What Is GPU Utilisation?
GPU utilisation shows how much of your graphics card’s processing power is currently being used.
It is displayed as a percentage.
Examples:
20%
The GPU is lightly loaded.
50%
Moderate workload.
99%
The graphics card is working at almost full capacity.
What Does It Tell Us?
High GPU usage usually indicates that your graphics card is the limiting component.
If GPU usage remains around:
95–100%
Your GPU is likely the bottleneck.
If GPU usage stays much lower while FPS is also low, another component—often the CPU—may be limiting performance.
Is 100% GPU Usage Bad?
No.
In fact, when you’re GPU-limited, high utilisation is expected.
A graphics card is designed to operate at full load when required.
The goal isn’t to avoid high utilisation.
The goal is to ensure the GPU is performing efficiently without overheating or throttling.
2. VRAM Usage
What Is VRAM?
VRAM stands for Video Random Access Memory.
Unlike your system RAM, VRAM is memory built directly into your graphics card.
It stores data that the GPU needs immediate access to, including:
- Textures.
- Shadow maps.
- Terrain data.
- Frame buffers.
- Cockpit displays.
- Cloud information.
The more demanding your graphics settings, the more VRAM is required.
Why Does It Matter?
If VRAM usage approaches the physical limit of your graphics card, the system may need to move data between VRAM and system RAM.
This can increase loading delays and contribute to stutters.
Monitoring VRAM usage helps you decide whether settings such as texture resolution or render resolution are appropriate for your hardware.
3. GPU Clock Speeds
What Are Clock Speeds?
The GPU clock speed is the operating frequency of your graphics processor.
Measured in MHz.
Higher clock speeds generally allow the GPU to complete more work each second.
Modern GPUs automatically adjust their clocks depending on:
- Workload.
- Temperature.
- Power limits.
Why Monitor Clock Speeds?
Consistent clock speeds during heavy workloads usually indicate healthy GPU operation.
If clock speeds drop unexpectedly under load, investigate whether the GPU is:
- Reaching its temperature limit.
- Reaching its power limit.
- Being limited by another component.
4. GPU Temperatures
Why Temperature Matters
As your graphics card works harder, it generates heat.
Modern GPUs are designed to operate safely under load.
Exact temperatures vary by model, cooling solution and ambient room temperature.
Rather than chasing a specific number, look for:
- Stable temperatures during long flights.
- Consistent clock speeds.
- No signs of thermal throttling.
If temperatures become excessive for your specific GPU, it may reduce clock speeds to protect itself.
Signs of Possible Thermal Throttling
- Clock speeds decrease unexpectedly.
- Performance drops after long flights.
- GPU utilisation falls despite demanding scenery.
- Fans running at maximum speed for extended periods.
If you suspect thermal throttling, compare temperatures with the manufacturer’s expected operating range for your graphics card.
5. GPU Power Draw
What Is Power Draw?
Power draw measures how much electrical power your GPU is consuming.
Usually displayed in Watts.
Higher workloads generally increase power consumption.
Why Is It Useful?
Power draw helps explain:
- Why fans become louder.
- Why temperatures increase.
- Whether the GPU is reaching its designed power limit.
Power draw should be interpreted alongside GPU utilisation and clock speeds.
6. MSI Afterburner
MSI Afterburner is one of the most widely used GPU monitoring tools.
It provides:
- GPU utilisation.
- VRAM usage.
- Clock speeds.
- Temperatures.
- Fan speed.
- Power draw.
- Frame times (with RivaTuner Statistics Server).
Although it also supports overclocking on compatible hardware, this course focuses on monitoring rather than changing clock speeds.
7. HWiNFO
HWiNFO is a detailed hardware monitoring application.
It reports information for almost every component in your computer.
Examples include:
- CPU temperatures.
- GPU temperatures.
- Motherboard sensors.
- SSD temperatures.
- Fan speeds.
- Power consumption.
- Memory usage.
HWiNFO is particularly useful when diagnosing complex performance or stability issues.
8. NVIDIA App Performance Overlay
The NVIDIA App includes a built-in performance overlay.
It can display information such as:
- FPS.
- GPU utilisation.
- GPU temperature.
- GPU clock speeds.
- CPU usage (depending on configuration).
- VRAM usage.
This is a convenient option for users who prefer an integrated monitoring solution without installing additional software.
9. Monitoring a Complete Flight
The best way to understand your system is to monitor an entire flight rather than a short benchmark.
Observe performance during:
Pre-flight
GPU idle behaviour.
Taxi
Airport complexity.
Ground traffic.
Initial scenery loading.
Take-off
Rapid scenery loading.
Cloud rendering.
GPU load increases.
Cruise
Lower airport complexity.
Stable utilisation.
Approach
Photogrammetry.
AI traffic.
Airport detail.
GPU workload rises.
Landing
One of the most demanding phases of flight.
Compare GPU utilisation, VRAM usage and frame pacing with the cruise phase.
Interpreting Your Results
Ask yourself:
Is GPU utilisation consistently high?
If yes, your GPU may be the limiting component.
Is VRAM close to full?
Consider whether texture-related settings are appropriate for your graphics card.
Are clock speeds stable?
If not, investigate temperatures or power limits.
Are temperatures stable throughout the flight?
Large increases combined with falling clock speeds may indicate thermal throttling.
Does GPU usage suddenly fall while FPS also drops?
This may suggest the CPU or another system component has become the bottleneck.
Common Myths
Myth 1
“100% GPU usage is bad.”
False.
A fully utilised GPU is often exactly what you want when you’re GPU-limited.
Myth 2
“Lower temperatures always mean better performance.”
False.
Modern GPUs are designed to operate safely under load.
Focus on stability rather than chasing unrealistically low temperatures.
Myth 3
“VRAM only matters for 4K.”
False.
High-resolution textures, detailed scenery and complex aircraft can increase VRAM usage at many resolutions.
Myth 4
“If GPU usage drops, my graphics card is broken.”
False.
Low GPU utilisation can simply mean another component—often the CPU—is limiting performance.
Student Exercise
Today you’re going to monitor a complete Microsoft Flight Simulator flight.
Step 1
Choose one monitoring tool:
- MSI Afterburner.
- HWiNFO.
- NVIDIA App Performance Overlay.
Step 2
Load your Module 1 benchmark flight.
Use the same:
- Airport.
- Aircraft.
- Weather.
Step 3
During the flight, record:
- GPU utilisation.
- VRAM usage.
- GPU clock speed.
- GPU temperature.
- GPU power draw.
- Average FPS.
- Frame consistency.
Record these during:
- Taxi.
- Take-off.
- Cruise.
- Approach.
- Landing.
Step 4
Review your data.
Identify:
- Was the GPU fully utilised?
- Was VRAM nearing capacity?
- Did temperatures remain stable?
- Were clock speeds consistent?
- Did the GPU appear to be the limiting component?
Student Checklist
Monitoring software installed.
GPU utilisation understood.
VRAM monitored.
Clock speeds analysed.
Temperatures reviewed.
Power draw observed.
Full flight monitored.
Results recorded.
Lesson Summary
Congratulations.
You now understand how to monitor and interpret your graphics card’s performance in Microsoft Flight Simulator.
Remember:
- Monitoring provides evidence, not guesses.
- GPU utilisation helps identify whether your graphics card is the current bottleneck.
- VRAM usage indicates how much graphics memory your simulator requires.
- Stable clock speeds and temperatures are signs of healthy GPU operation.
- Power draw helps explain how hard your graphics card is working.
- Tools such as MSI Afterburner, HWiNFO and the NVIDIA App Performance Overlay allow you to monitor these values throughout an entire flight.
- By combining these metrics with the CPU monitoring techniques from earlier modules, you can accurately diagnose many performance issues and make informed optimisation decisions.
Knowledge Check
- What does GPU utilisation tell you?
- What is VRAM, and why is it important?
- Why should GPU clock speeds remain relatively stable under load?
- How can temperature affect GPU performance?
- What does GPU power draw indicate?
- What are the strengths of MSI Afterburner, HWiNFO and the NVIDIA App Performance Overlay?
- Why is it better to monitor an entire flight rather than a short benchmark?
- How can monitoring data help you distinguish between a GPU bottleneck and another system bottleneck?