If price is no object, you can go for nvidia gtx 680 or radeon 7970. That depends on what games you usually play. If you are into FPS in the likes of Metro 2033 or Battlefield 3, you will certainly need all the graphics muscle you can get. But these cards will set you back around 25T up. If you want slightly lower specs, you can go for radeon 7950 or gtx 570. 1920 x 1080p is already a high resolution gaming. If you enable anti-alias, you will certainly require very powerful cards. Even if you are a light gamer, I do not think you will be happy if your cards can only do 30 frames per sec. It is so strenuous on the eyes. Your target should be no less than 45-50 fps. Ideally, 60 fps should be your target as it delivers buttery smooth gameplay.