I'm just wondering, if I buy an SLI or crossfire ready motherboard, does that mean I can only an nvidia card on an SLI mobo, and ATI on a crossfire board? Or can you use any PCI-E card in the single 16x slot?
You can use any brand video card in any motherboard with a PCI-e slot. If it's a SLI board then you have to have 2 x Nvidia cards in it to run SLI. The same for Crossfire = 2 x ATI cards. For a single card setup it doesn't matter which brand of card you've got.It will work.