Well I'm running one of Nvidia's most current drivers at the moment 169.21 to be exact and I'm not having any graphics propblems like that.
I also play F.E.A.R. ,Half-Life 2 and Oblivion without too many issues either.
I'm using two 7800 gtx cards that are right below the 7900 you're using too so it should be ok to use this driver with that card.
One thing I would highly recommend is that you use the Driver Cleaner Pro program to clean out your drivers on your computer BUT make sure you read the readme in there before you use it.
http://downloads.guru3d.com/download.php?det=745