Check the diagnostic light, which may have some info:
http://support.dell.com/support/edocs/systems/ws650/en/ug/advanced.htm
The F12 key should give you access to a complete suite of tests which
may help as well.
(Boot to utility partition).
This sounds like a possible overheating problem, so check that the
fans are running and clean the inside thoroughly.

On Fri, Jun 5, 2009 at 2:22 PM, Donald DeWitt<[log in to unmask]> wrote:
> Booted up computer today and it ran normal for about ½ hr. and then suddenly
> shut down. First the screen went black, then there were 4 or 5 beeps coming
> from the tower, and finally a sound like the hard drive was spinning out
> control that lasted only a short time. Rebooting resulted in a blue screen
> stating Windows was shutting the system down. Using the F12 key I entered
> into a page that let me do a Hard Drive Diagnostic test. The results
> revealed – “Pass”
>
>
>
> This computer is a 5 year old Dell 8400 running XP. I have not added any new
> software or hardware recently and I do a daily run with AVG and Super anti
> spyware.
>
>
>
> Do you have any suggestions what the problem might be?

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