Every PC has a bottleneck somewhere. It only matters when it stops you reaching the FPS you want.
Quick check: pick your processor and graphics card in the bottleneck calculator to see which part limits FPS and by how much.
What a bottleneck means
In a game, the processor prepares each frame (game logic, physics, telling the graphics card what to draw) and the graphics card draws it. Whichever part is slower sets your FPS:
- CPU bottleneck: the processor cannot prepare frames fast enough, so the graphics card waits. Common in esports games at high FPS, big strategy and simulation games, and when a fast card is paired with an old processor.
- GPU bottleneck: the graphics card is working flat out. This is the normal, healthy state in most games at high settings, and lowering graphics settings raises FPS.
Signs of a CPU bottleneck
- Graphics card usage below about 90% in a demanding game, with FPS lower than you want.
- Lowering resolution or graphics settings barely changes FPS.
- FPS drops in busy scenes: crowds, cities, big battles, many players.
- One or two processor threads near 100%, even if total processor usage looks low.
- Stutter and uneven frame times (poor 1% lows) more than a low average.
How to check in two minutes
| Method | What to look at |
|---|---|
| Task Manager (Ctrl + Shift + Esc → Performance) | GPU usage and CPU usage while the game runs in windowed mode |
| NVIDIA app overlay, AMD Adrenalin metrics, or MSI Afterburner | GPU usage live in game; Afterburner can also show each processor thread |
| Resolution test | Drop the resolution or render scale a lot. If FPS stays the same, the processor is the limit. If it rises, the graphics card was the limit |
Check in the game you actually play: the same PC can be processor-limited in Counter-Strike 2 and graphics-limited in Cyberpunk 2077.
How to fix a CPU bottleneck
- Raise the resolution or graphics settings. It sounds backwards, but if the graphics card is idling you get better image quality for free, with little or no FPS loss.
- Cap your FPS a little below what you get in busy scenes. Steadier frame times feel smoother than a high but uneven average.
- Close background apps such as browsers, launchers and recording tools that compete for processor time.
- Lower processor-heavy settings: crowd density, view distance, physics and simulation detail.
- Turn on XMP/EXPO and use two RAM sticks. Slow single-channel memory makes processor bottlenecks worse. See how much RAM you need.
- Keep it cool. A hot processor slows itself down. Clean the dust and check the cooler.
- Upgrade the processor, if the steps above are not enough. Check that the new one fits your motherboard socket, and compare options in the bottleneck calculator.
How to fix a GPU bottleneck
Usually you don't need to: it means your PC is using the graphics card fully. If FPS is too low, lower the heaviest settings or use upscaling (see how to increase FPS), or compare a faster card in GPU vs GPU.
