This is typical of the common "failing motherboard capacitors" issue. To verify the issue, you have to inspect the motherboard capacitors for bulges and leaks. Here's a web site with pictures and more about the issue.
http://www.pcstats.com/articleview.cfm?articleID=195
The good news is that vendors when you pummel them with this issue replace the motherboard at no cost.
Bob
When I start my computer the Windows XP screen comes up then it goes black and says no signal. It then goes to a screen that says,"We apologize for the inconvience but Windows did not start properly.A recent hardware or software change might have caused this".Then it gives me options on starting windows and it also goes into a 20 second countdown before it tries to start windows again, some times it works sometimes it doesn't. This doesn't happen all the time but this morning it did it four times in a row. How do I fix this?
Chowhound
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GameFAQs
GameSpot
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TechRepublic