[squidgyb]

In all honesty I doubt that it's the GPU - or the CPU, in an odd way. I have a tendency to go off on tangents while trying to explain something I think I understand, so try to bear with me...

It's mainly the CPU, but in most cases just turning up the CPU won't help you beyond a certain point - the same is to be said by the GPU. There are a lot of... knots... in the code - think of it like a huge machine that has been having wire upon cable upon wire plugged into it day after day, for, well, 4-5 years. These cables get tangled, and what the devs are currently doing is untangling the cables.

If the cables were all straight and laid out perfectly in parallel, all cores on a PC could run 100% as the "machine" is being supplied constantly from all the cables.

Ah, I'm a little bit drunk on a Friday night and I fear that I'm becoming as nonsensical as raaaid (sorry raaaid, I love you but sometimes you make littel to no sense!).

What I'm trying to say is that if the code gets all straightened out, and all the loops, dud ends, and "knots" get cleaned out, then it should use as much of the cpu as it can. Because it's a complex beast, and has to do a hell of a lot of calculations, in parallel, and provide the results of those calculations to the GPU, so it in turn can make sense of the results and show them in a pretty display on the screen for you. In reality it will never use 100% of every system in any given PC, because some part of it will hold the other bits back. Which part does this will depend on the quality settings in the nvidia control panel and CoD, the speed of your CPU/GPU, background processes, and a myriad of other things.

There's a lot going on in there, you know.