See if the system is turning off the hard drive and/or monitor after a timeout period. Set these to "Never" if they time out. USB hard drives can also spin down after a timeout period but some of these have arcane configuration methods. XP, when running, will periodically check that drives are accessible and can post that message if one is not. I have had that happen with an internal drive that had an intermittent power connection so that could be another possibility.
I resolved my last issue with the overheating by thoroughly cleaning my computer and replacing the heat sink compound.
Now when I leave my computer and come back a few hours later, I have a black screen. The computer is still running, but not responsive. I have to use the power button to turn it off and back on.
I have looked at event viewer and found the following 2 alerts:
Event Type: ErrorEvent Source: DCOMEvent Category: NoneEvent ID: 10010Date: 12/26/2011Time: 8:27:06 AMUser: NT AUTHORITY\SYSTEMComputer: BROOKSHPDescription:The server {4EB61BAC-A3B6-4760-9581-655041EF4D69} did not register with DCOM within the required timeout.For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp.Event Type: WarningEvent Source: DiskEvent Category: NoneEvent ID: 51Date: 12/25/2011Time: 4:50:13 PMUser: N/AComputer: BROOKSHPDescription:An error was detected on device \Device\Harddisk1\D during a paging operation.For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp.
I have Windows XP SP3, Pentium 4 processor, 1.99 GB RAM. 413 GB free space.
I updated my drivers and everything was running fine until about 3 days ago. I am at a loss as to what is causing this problem. Please help me figure this out. Thanks

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