The reason I'm asking this is I plan to purchase a new gtx 770 upon release and SLI it in the future (gtx 770=updated gtx 680), BUT I dont wan't to have to upgrade any other components to do so. I'm currently running a corsair tx750 and It powered 2 gtx 660ti's very well, but I'm unsure of the power draw of the 680 vs the 660ti