Crysis is unplayable.

[Diabeetus]

Every time i play Crysis, I get fps and gpu usage that keeps fluctuating. Because of this, the game is unplayable. i am playing at 1080p very high settings. However, crysis 2 is very playable at a mix between extreme and ultra settings 1080p dx11 with high res textures with fps that ranges from 30 to 40.
This is my pc specs:
Gtx 560 1gb stock clocks
Amd athlon ii x4 630 2.8ghz
6gb ram DDR3

[miles82]

Crysis 2's engine is more optimized for consoles and thus lesser hardware can run it easier. On the other hand Crysis 1 has DX10 support but it's not optimized for it so it runs horribly with it. You will get significantly better performance with DX9 and if you download Xconfig or another config creator of the like you will have just as good a graphics as DX10 but with better performance and those configs are also optimized too so you'll get better performance on top of that. But your processor is a little on the slower side so it could be a bottleneck too.

Just so you know though, the main difference between Cryengine 3 and Cryengine 2 is deffered and nondeffered lighting. Deffered lighting are non complex lights which allows many more with about the same performance while non deffered lighting has much more complex lighting and is very taxing. Turning the shaders down you will notice a large difference in performance in Crysis 1 for this reason.