Thanks to all who responded to my problem.  The first time this happened, the shop too thought it was a video card fault so the first thing they did was put in a new one and still got the same beep sequence with no video.  They have never said anything about a possible memory problem.  The PC has an 80gig hard drive, 512mb RAM and is running WinXP Pro with all the updates.  So far, simply reflashing the BIOS has fixed things, at least temporarily.  The shop says it is not the video card that is faulty.

Frank mentioned possible overheating.  That is why I put in my original post about the computer being off prior to the first 2 crashes.  I was hoping that that would eliminate the possibility of overheating.  The shop still has my computer and I have not heard anything from them on it.  They seem to be baffled so I thought I would throw out the problem here.

Thanks,
Cindy Sanderson

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