problems with gf 6600gt drivers

so currently im replacing my old radeon with gforce 6600gt and im having the following problem.

ive installed the card properly inside the computer so i doubt the problem is there, but some reason i cant get it to install drivers.

i've properly deleted old drivers, booted in betwee, installed wrong drivers first accidently :P (gforce serie 9 drivers) and deleted those, rebooted again and now when im trying to install right one, gforce serie 6 driver, it wont let me. it keeps whining that it "cant find compatible video card" , tried with older and newer versio of the same driver and all of them does the same, yet the serie 9 one didnt error anythnig at all, exept refused to work properly (every 3d picture exploding basicly all around the screen).

so, anyone could support me abit that where the problem could be at?

You could try taking the card out, and booting without it, then putting it back in, and booting with it, then installing the drivers. That way windows would have to re-recognize the card.