I recently bought one of these and this is the problem i am getting:
I recently purchased the BFG 7900gt oc 256mb from you and have since installed it into my pc. The graphics card works fine for a few seconds then it rapidly dropped in fps in games such as Call of Duty 2. I then researched it and it was recommended that i needed a higher psu. I then purchased a 650w psu and the card is still the same. I then took out the 7900gt and put back in my radeon x600 pro and it works fine and has the same fps if not more than the 7900gt. As i know this should not be happening, and i was wondering what you could advise me to do? Thanks for your help in advance.
(this is the query which i just did to overclockers)
quite right, if you are able to swap the x300 and 7900gt back and forth that way it sounds like you havn't entirely wiped out the ati drivers. Make sure all remnants of that ati driver are gone, reboot then install the nvidia ones.