Having the same problem here. there are a few times when it shuts down when I log back in and then there are times when it works grate. What gives??????

yeah i can't figure out why it just craps out.. I thought it was when I did windows update, but then it happened after a screen saver and then after that I couldnt get it to start back up. The only way I got it to restart was to do a system restore.. It might be my video card driver b/c it has given me an error before after a screen saver but other than that i can't figure it out.