Ok, you need one of the latest beta drivers, I'm using 177.41. These will work just fine for the G92 cards and up but need a modded .inf file to install on the G92 8800's. Once you have that driver installed then install the physx software from the nvidia site. You should then be able to open the physx control panel and select GeForce for physx. More info here:
http://www.overclock.net/software-ne...-released.html