Ok im just using fear as an example, but my pc really dosent run how it should graphically. My friends computer isnt the greatest but it's still pretty decent, his results were slighltly below me for fear. But when he runs everything on high settings with max graphics he gets an average of maybe 80fps and everything runs lovely.
When i play fear and i run tests with everything on max i get an average of 20fps and a minimum of like 10fps (we both run at 1280 x 1024). Basically it runs like crap and it's the same with all the other games i play. For example i play warcraft quite a lot and i get a max of 30fps and get a lot of lag when in raids and when i have such a expensive and high quality graphics card i kind of expect my games to run perfectly.
I'm not quite sure what to try and wonder why my pc seems to never run anything above 30-40fps... I want to play the games i buy smoothly, and the lab tells me they will run perfectly and then i am dissapointed

Spec:
Geforce 7900GT 256mb
Amd 64 3200+
2Gb corsair ram (2 x 1gb)
Nforce 4 mobo
I have the latest drivers for both motherboard and graphics card and so have no clue what else to try other than a format which may not change anything and takes a long time.
Help would be really appreciated.