Hi. Im a Presario Cq40-401AU user.. I stacked it with a corsair gaming memory 2 + 2 GB 800Mhz ram. I can run games like Warcraft ( high settings no lag) COD4 (med settings), COD5 (med settings but not all) Hellgate London Med settings. Installed vista ultimate 32 with no fail.. quite satisfied. the speakers is loud also.. hehehe...