My issue is similar since it related to low fps, but it is different in a strange way. Essentially, I get the same fps no matter what settings I use. If I play on low, I get 15-20 fps. If I play on ultra, I still get 15-20 fps. Vsync is off and it normally averages 18fps. I have seen it once spike to 30 but that was it, just a spike.
My CPU never goes over 29% usage, it never uses over 1.2GB of RAM and my GPU is almost always below 45% but sometimes spikes to around 75%. Since its not even using all of my resources overclocking did nothing when I tried. Adding my second video card back in to do crossfire also does not help. I am running a Phenom II x6 1100T Black, so 3.3GHz with 6 cores. I have 16GB (I know, useless, but it was free) of DDR3 ram and normally a single HD Radeon 6870 (2GB version) but can add a second for crossfire.
I have tried forcing vsync and also forcing it off with my video card which had no effect. No matter what I change the settings to, the fps stays within the range except for the rare spikes in both directions which normally happens when the map is loading fast. If I drive a car and hit 100km/h or try to fly a helicopter for instance my fps will drop to 10 and not go up. Ultra settings, 10. Low settings, 10. Doesn't matter what I do, I am simply stuck with this terrible FPS despite my computer easily beating out many other people that run the game fine.
From what I have seen in the thread there is a serious issue with both multiple cores and AMD in general but I figured I would post anyway since my issue is slightly different with the whole same fps no matter what, rather than simply low fps like many of the other people in this thread.
