[Luckeh!!!!]

what graphics cards have you tried so far?

btw I have no idea why the GFX card would work but not the fan, could be the fan has failed, even on your other gfx cards. You could test them in a m8s comp to see if the fans work.

Other than that.... you are putting yout GFX card in danger of overheating and causing machine lock-ups. (unless it is able to run passively)

I'd stick a fan on your heatsink temporarily (one that plugs into your mobo)