installed vga silencer, flashed ati 9800 pro 256 (360 core) to 9800 xt, it works with all 3 bioses (ati, sapphire, hercules), but i get artifacts in high-end 3D games like ut2k4, far cry, nfsu, battlefield, 3dmark.. i flashed back to original backup bios but i still get artifacts.. what can i do..