actually, there are MANY threads on stability issues, and I've had my own too....thery seem to be due to power issues, when the card swtichs from its 2d core clock (400 mhx) to its 3d core clock (425 mhz) like when the elevator door opens in a Doom 3 level....when it ups the freq, it requires massive amounts of power...the solution is to rause the 2d clock up to 425, but this DOES bring up yor temp! Alll in all, the 6800 U rocks, and will have a longer life to it in furutre games where the X800 will not becaus eof one thing: Pixel Shader 3.0....a difference of 600,000 shader instructions! I'd take the 6800U (and I did)