IMO, id just get one high end card. Wait for 512mb GTX, and see how it does. it it beats the 1800XT, go for it. SLI, and Crossfire really aren't worth it, especially Crossfire, at this early stage, and SLI only supports a handful of games, and some don't have that bigger improvments. Thats why i think 4 GPU's, it going to be retarded. it will be about as efficient as a fish on a bike.