Hey guys im looking to upgrade my graphics card as i only have a nvidia gt 530 which offers poor performance for gaming i was thinking of buying a asus 2gb 7770 card however my psu is only a 460watt so im not sure if i would have enough power available to use it with the other parts of my pc which are a i7 2600 @3.40 quadcore 6gb ddr3 ram,2tb harddrive