What Is CPU Bottlenecking?

[h3llfire741]

I know it's when the CPU is holding the rest of the system from delivering the power that it should. For example, I have an FX-8150 and a GTX 970. I heard that it might bottleneck, but how can you tell that it is being bottlenecked. Are there signs I should be looking for or is the FPS generally lower?

 

[InvalidError]

Bottlenecking means your FPS is being held back by one component in particular.

If you play a game, CPU usage monitoring says one of the game's thread is pegged at 100% CPU usage while the GPU is well under 100%, that game is predominantly CPU-bottlenecked. If none of the threads are pegged at 100% but the GPU is close to 100%, then you have a GPU bottleneck. If neither reaches 100%, you are likely locked at vsync and then your display is technically the bottleneck.

 

[iam2thecrowe]

Basicall the definition of a bottleneck in terms of pc hardware performance, is the component that is the limiting factor in performance. In your case, your CPU is going to be the component that limits your performance (assuming your playing at 1080p).
To determine a cpu bottleneck there are a couple of things you can do. load up a reasonably hardware demanding game, run it at your monitor's max resolution with vsync off and your desired in-game detail settings and note the fps. Now drop the resolution significantly, by at least half (leave detail settings alone as they can affect both cpu and gpu). If you have a cpu bottleneck you should notice minimal changes in fps by dropping the resolution. If it were a gpu bottleneck dropping the resolution by half should give a significant fps boost.