I have an E-machine T2692.
My PC began a strange behavior about 10 days ago, ran fine for 2 years prior. Everything runs correctly except when I shut it down. The normal shutdown using windows shutdown command appears to proceed normally such as "windows is saving your info" then "windows is shutting down" followed by "no signal". The new weird behavior is the power supply fan increases speed (determined by sound) and the hard disk light comes on full (no blinking). It will remain in this condition until I unplug the system. The old shutdown behavior was for the entire system to become completely quiet with no hard disk light on which tells me everything is turned off correctly. (I don't guess the weird behavior is a huge issue unless I forget to unplug it and let the hard disk spin for days.)
Over the weekend, I used the e-machines support chat line where they had me reset my BIOS, pull the battery off the main board for 3 hours, reset a number of other SW type things. None of their suggestions corrected the problem. I am beginning to think that I have a hardware problem. How can I check it out before buying a new power supply? I know that the SW shuts down the power supply, so I suspect that a signal is held in an ON condition erroneously.
Is there a simple voltage check that I can make when it is in this weird condition to verify the failure?
PS: The fan on the uP (separate fan from the Power Supply fan) is not running in this weird state so I am confident everything has shutdown except the power supply and the hard disk. I can hear a very quiet high pitch sound that I am sure is the hard disk spinning during this weird condition.
