I have a Quadro 600 here that is more or less collecting dust. I also have a slot free. So I'm thinking to plug it in and use it as dedicated PhysX card along with my two 660ti. Can i do that, or would it be driver chaos ?
I'm no expert but I think it would be bothersome. From what I garner Quadro cards run mainly under OpenGL and optimised for OpenGL, where as your Gefroce although runs both is primarily a DirectX device. So the two may interfere with each other ?
Mixing usually causes chaos with professional applications, I don't recommend using it though as it will more than likely hold back your SLI 660Ti's.
Quadro Cards are for Graphically intense business applications and are not really meant for gaming. Also the Quadro card might slow down the performance of your 660TIs.