I got a 6950 and i was thinking about some other upgrades because i got an offer on my old system. I want to run my 6950 as my main card but on my new system i want to also use my older 9500gt nvidia card to do physx. I am wondering if i could get some input on exactly how this works. Do i need special software or just instal drivers for both cards?
You should be able to install the nVidia card down lower on the MB (somewhere it will be detected as card#2 or higher).
Install the nVidia software, and under PhysX settings - switch it from Auto to GPU (specifying the 9500)...
That should be it.