I have a decent PC but for some reason I am getting frame rates from 10-25 per second. I have everything except Heat Blur on max and am running at a resolution of 1280x1024, and I don't have any AA or AF enable in ATI's Catalyst Control. Here are my PC specs:

AMD X2 4800+
4GB RAM
500GB Hard Drive
ATI 3870 with 512MB
Creative X-Fi
Windows XP Pro SP3 and Vista Ultimate SP1 (64-Bit)

Shouldn't I be getting over 60 FPS? I just formatted my drive and have all of the latest drivers install, and I have tried both XP and Vista but it does not seem to make a difference. I can play Battlefield 2 and COD4 with everything maxed and have no problems, so what is causing this?

Thanks in advance for any help.