I just installed this motherboard "ASUS M2N-SLI Deluxe Socket AM2 NVIDIA 
nForce 570 SLI MCP ATX AMD Motherboard" and I was wondering if I needed to 
have 2 Nividia Video cards to run in SLI or could I use two ATI cards?

Off the cuff answer it will have to be 2 Nvidia cards
SLI is their solution for 2 graphic cards
Crossfire(? may not be called that now) is ATI's 


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