The most common bottleneck that you'll see in PC gaming is a CPU bottleneck, meaning that your CPU
will be restricting the potential number of frames being drawn from a GPU.
The simplest explanation for how this happens is that your CPU is just not powerful enough to keep up
with your GPU.
But let's dive a little deeper and take a look at what's really going on.
Let's see that we have a game being rendered at 60 frames per second, which is equal to one frame every
16.6 7 milliseconds.
The CPU, in addition to many other tasks, has to prepare sending a call to the GPU, which means it
is sending some data such as texture and shaders, whilst also rendering objects and buffers on the
next frame which is to be rendered.
The GPU renders this frame and it's then displayed onto your monitor when it receives the next frame,
which is to be rendered and while thus rendering the CPU is already on the next frame for the GPU.
So here we have no bottleneck, and that's because the CPU is preparing the frames faster than the GPU
can render them.
As mentioned earlier, in case the CPU is on the weaker side, then the GPU will be rendering frames
faster than the CPU can prepare them.
And this right there is the bottleneck.
Your GPU could be utilized 100% if your CPU was more powerful, but in this case it spends more time
idling.
Are not rendering frames because of this bottleneck situation.
Let's see if GPU can render frames every 16.6 7 milliseconds, but the CPU needs 25 milliseconds to
prepare them.
Now, in this 25 millisecond duration, the CPU is doing a lot of work In addition to preparing the
frame data for the GPU, it also needs to possess other things such as any game, AI, logic, physics
and of course any other background tasks that may be occurring in other programs.
All these tasks increase load on the CPU and can therefore increase the amount of time that it takes
to send a call to the GPU.
Essentially, this is why some games are more CPU intensive than others, such as Battlefield five,
which is quite CPU intensive.
See, and that is a lot of network data, game logic and physics to handle, whereas riding your horse
to first in Witcher three is a lot less CPU intensive.