Okay, I have a ATI 4870 as my main card. My mobo only supports 1 PCI-e slot. My ATI 4870 is currently using it. I do have 2 PCI slots available though. I was looking at some PCI cards, and I came across a GeForce 8400GS 512MB Card. I really want to play Mafia II with physX on, but I cant because I need a PhysX card. So my question is. If I use my ATI 4870 as my Main card, Can I use the GeForce 8400GS 512MB as a Dedicated PhysX Card?. I don't see why this would not work... Also, I was not sure if it would work because the GeForce 8400GS 512MB is a PCI card, and my ATI is a PCI-e Card. I don't know if this would cause any issues. Here is the card I would be purchasing. http://www.canadacomputers.com/prod...item_id=023549&sid=0l612h55oblt6uvi9pcirsi5l0 Also I am quite aware there are drivers out there that let you use nVidia cards with ATI cards.