Trying to figure out what might be causing this with my main system. I'll be going along, playing, browsing, or nothing in particular, then - the screen goes black, and the computer reboots. This happens perhaps 2 times a week. I'm running XP SP3 with 1 GB RAM, an NVIDIA 8300 GS video card that is supposed to be 128MB (but insists that it is 512), and a 2.2 dual core processor (IIRC Intel Core 2). Is this a processor issue, RAM issue, power supply issue, or something else?