Firstly: how is the card at intense 3d gaming? is it stable? I got an MSI 5750 and i'm gonna break the damn thing due to a lot of hardlocks and the drivers just don't seem to be fixing the issue.
Secondly: Asus P6T SE doesn't support SLI, they didn't want to pay Nvidea extra money to support it, SE stands for slim edition or something like that and therefore reducing components and costs. So im afraid it only support Crossfire.