Ok, to make it short, I have all drivers and Vista updated, no sp1. For some reason I enable SLI in Vista and when I verify with GPU-z it state's that it's disabled. Also I run 3dmark with one card and both cards and I get some what the some benchmark. I've heard of people having this issue, not sure if it's particularly just with Vista 64bit. I really need some help. Or atleast some info that Microsoft might fix this issue.