I was looking around and found a folder of minidumps that all had dates corresponding to the times when I remembered my computer rebooting like this (three files all from the same day in february, when I couldnt' figure out why gimp kept making me reboot, up to one today)

Apparently they aren't supposed to be opened in notepad, but I did see kmixer.sys mentioned several times. I went to the system event viewer and found the logs for them, which were only labelled as information >:[ I would say this is more of an error than my mom's computer trying to become the master browser or whatever.

Anyways, here's what they said

Event Type: Information
Event Source: Save Dump
Event Category: None
Event ID: 1001
Date: 7/31/2006
Time: 5:10:19 PM
User: N/A
Computer: DIE
Description:
The computer has rebooted from a bugcheck. The bugcheck was: 0x0000009c (0x00000000, 0x8053f0f0, 0xa2000000, 0x84010400). A dump was saved in: C:\WINDOWS\Minidump\Mini[date]-01.dmp.

For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp.

stu thinks it's something to do with my PSU and voltages, but i'm just generally lost. Apparently the only other person on the entire internet with this error is german though