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Dimension 8400 no power

by ron_cox99 / May 4, 2010 5:25 AM PDT

I have a Dell Dimension 8400 Home Media Edition Windows XP SP3.

Just recently I turned my computer off to give it a day of rest and had trouble getting it to turn back on using the power button. I had to keep trying to press the power button and it finally booted up. However, I turnjed it off again and now it will not power up. I had absolutely no problems prior to this.

I have replaced the CR2032 battery even though I had no trouble with configuration and date/time. I am thinking the problem is either the PSU or Power On switch. I do not know how to remove the front facade to get to the Power switch nor do I know how to test the PSU

I would appreciate some steps to take in troubleshooting this. Here are my symptoms:

I have plugged the power cord into a known good outlet to remove the power switches or UPS as being a culprit. No Change.
I have Reset several boards such as video and TV tuner (these were in my way to get the the CR2032 battery). No change.
There is a little green LED on the mother board that comes on when power is plugged in, goes out when unplugged.
There are no Diagnostic LED lights at the rear of the unit. They do not flash or give any indication of ever lighting up.
The power on button does not light up at all.

What is the best way to proceed?

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Just links and research.
by R. Proffitt Forum moderator / May 4, 2010 9:03 AM PDT
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Dell Dimension 8400
by ron_cox99 / May 5, 2010 2:06 AM PDT

That was the first thing I tried and was flooded with all kinds of variations and only on instance that was close to my situation. That was after reading post after post. They all were like mine but most had diagnostic lights or power on lights. I had neither. I will continue to goggle some more.
Thanks for your help.

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Please your help needed
by duse7 / December 30, 2010 3:20 AM PST

hi ron Icame across this posting from may on your 8400 with no power. I have the same symptoms exactly. I do suspect the on/off button. what was the final prognoises with your 8400? any help would be great. If possible email me at icec777@aol or here if I can remember how to get back here thank you and happy new year Frank

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Same exact problem here
by DaveCarrera4 / November 18, 2012 5:26 AM PST

Since this is the closest issue to what I'm having - I'm keeping the thread alive. Same story - little LED lit up green on mother board, no lights on front, no diagnostic lights on back - but this PC is now nearly 8 years old - thats 56 years old in a dog's life...

Ordered a new power supply - 500W this time. Hopefully that does the trick.

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