Im going to get the ATI R600, but i hear of a R700.

[Geoff]

Ok.. now i just have to ask.. what game doesnt support SLI?

Well besides the fact that pretty much all older games dont support it, here are some that dont:

http://www23.tomshardware.com/graphics.html?modelx=33&model1=531&model2=530&chart=201
http://www23.tomshardware.com/graphics.html?modelx=33&model1=531&model2=530&chart=222

There are alot of other games out there that dont as well, and some games do support it, but the improvement is so minimal, it wouldnt be worth the extra money.