I am currently able to grab a stock evga 660 ti for 150 bucks, but I have a bit of trouble. Does my psu, an ocz stealth xstream 2 support it. It has 2 6 pin power connectors currently plugged into my other card right now (6870 radeon) so I know that will work. But im not sure if the power supply is compatible/powerful in general. Urgent help would be so great, thanks!