My currents specs are: Asus P5N-D 750i Sli (2x Pci-e x16 2.0),Core 2 Duo E8400, 8800 GTS 512,2GB ram 800 mhz, 600 watts power supply.Is buying a second 8800 GTS a good Idea? I saw some reviews with 2 x 8800 GT's beating one GTX280 and 2x8800 GTS are better than 2 GT. Is buying a second 8800 GTS 512 a good option ?