Thanks Meister. It seems like it will, and possibly the only way to know for sure is to test it out myself. I just wanted to get a good idea of what I'm in for (The gpus are being mailed). The reason I ask is because I've been having some crashing coming from steam's civ5 game. I looked it up and undid any overclocking I've done, hoping nothing is wrong with my 460 card. I think I will try both sli 580 and sli/physx 580/580/460.
I love learning about computers