K so Nvidia, have u installed the latest Vista drivers? this might help. What im about to say next is a contradiction on that last statement
IF u have installed the latest drivers, try going back to the ones before them , when i installed the latest ones my performance dropped dramatically, However some people have had opposite reactions, so hence the contradiction lol, if u havent installed the latest Nvidia drivers, try them
Wow hope that made sense lol.
Also the drivers suck, and they will do for a little while yet until Nvidia pull their fingers out. So i guess u will have to put up with it, the 6800 shud be able to handle Vista fine.