Also, for anyone interested, you can run NVIDIA SLI on some crossfire only boards. Requires a bios mod for your motherboard. Also, some MOBOs support using an AMD and an NVIDIA gpu in a SLI type hybrid mode. I forget what it's called at the moment though. Hydra or something. I'm not sure if they still make/use this technology though, as it wasn't as good as pure sli or crossfire setups. You could use pretty much any mix of PCI-E cards though. Didnt have to be the same chip or anything.