I have a pc running windows vista ultimate. The problem is whenever I try to play a game (doesn't have to be one with good graphics) it starts to run very slowly. So the question is, is it the graphics card or my processor or both. The graphics card is a Powercolor ATI Radeon 9550 Pro 256MB, the processor is an Intel Celeron 2.60GHZ. I have 1536MB RAM too. Thanks for any help.