As you can tell, this is the BSOD for windows vista. Sorry if I can't provide much details, but I'll try my best. Sometimes (actually most of the time), this happens. I would have my com becoming laggy, then a hang, followed by a reboot. The entire episode lasts for around 10 secs. When music is playing, the music skips and lags during this time. Most of the time, the computer reboots without anything special happening, sometimes, it will produce a blue screen upon start up, with "physical memory dumps" or something to that effect, with c000021a Fatal System Error. This lag, hang and reboot doesn't happen when I do things such as surf the net or watch videos, but when I play those graphics-heavy 3-d games, the likelihood of such occurences shoot up. I tried a registry cleaner (Regcure), which tried fixing errors. It seems like there are always some problems in the Empty Registry Keys part no matter how much I try to fix it. I also do not have the vista disk with me, so a solution that doesn't require the disk is also welcome. Thanks for the your answers in advance!