Let me first say, nice setup you have there.
My thoughts are that at least some of the blame is on Vista. The video drivers for Vista are still in a pretty primitive state, and aren't that great performance wise.
Ok, try something for me here. Pump up the resolution on FEAR. I mean, max it out (do whatever your monitor can do.) Do max AA/AF. Then, tell me what the FPS numbers are. If they are the same/close to the same, then the processor is actually being the limiting factor.
Also, make sure that your ram is running in dual channel mode. I know, that seems like a stupid mistake to make, but it does happen. Open up CPU-Z and see what it says about your ram.
yah i think your right.. cause i was running at 1.86 ghz getting about 30 fps.. when i overclocked to 2.6ghz i was getting 80-150 fps... must of been my core 2 at 1.86 limiting me??
Best of Luck