Both of those are real good cards with excellent cooling. You listed a GTX 560 and 570, though, not a GTX 580. Your power supply is more than enough for any of the 500 series cards. The Gigabyte GTX 560 SOC you listed is out of stock, and has been for quite some time (which hopefully means that it will be back in stock soon). To reach your target FPS, I would recommend the 570. Although the 560 SOC is clocked at 1000 mhz and is nearly as good as the 570, you can also overclock the 570 to reach even higher levels of performance.