Ok I've already put a post about this before but my system has got steadily better. Originally my system used to almost instantly lock up when burning DVD's and playing games, after doing a diskcheck operation and installing new ram I've managed to solve the DVD burning issue, and I can play games better, however I still encounter frequent lockups when playing games. Basically, when playing Counter-Strike or GTA San Andreas, I can usually play from anywhere between 10 - 60 minutes without the whole system freezing up but I cannot for the life of me determine what is happening with my GFX card. In various parts of the games, (usually in a dark corridor or room) I can see a lot of artifacts floating about, but in other parts of the games there aren't any. I've tried overclocking the GFX card, turning on fastwrite, and changing the aperture size but still there is no difference, and the games seem to lock up randomly. I doubt very much that its a heat issue because my model is the HIS version and so comes with a rather large heatsink attached on the same side of the card as the fan. Is there anybody out there who knows how to fix this? Its driving me insane!!!!!!!! All help appreciated.