About 18 months after installing XP Home on my office machine I had the same trouble.  Micron replaced the power supply and mobo, both reasonable sources of the problem, but it continued.   Ultimately, I traced the problem to a conflict between the NVidia drivers installed by XP; that is, when I visited the graphics board website, downloaded their most recent updates/drivers, and installed them (telling XP, yeah, I understand their not "certified"), the problem was solved.  I had tried the idea of unchecking automatic in "Startup and Recovery" (which is good idea) but only the graphics drivers seemed to solve the problem.  Also, if you're running GoBack, double check and make sure your GoBack recovery files are not corrupted (start GoBack and see if there are recovery points), but this at one point was also part of the problem.  Power supplies are often the culprit, and there are so many possiblities.  Not sure any of this will help, and good luck.  I KNOW what a hassle this problem is.

Ed Nottingham

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