I was working on an old 865GLC desktop when it powered off.

[DanielFranco]

Desktop PC not Powering up.

I was working on the 865GLC unit when it powered off, It had been making a little extra fan noise for a few days. The power LED was dimly visible. I concluded that the power supply had probably failed.

I replaced the power supply with a new one. But the unit still does not power up. Although there is an led on, on the mother board.

There were no error messages. It simply powered off once and I have not been able to power it on again.

 

[C12Friedman]

Start by resetting the CMOS clock, see if any joy then

 

[hang-the-9]

If all the power connections are good, check the motherboard for issues with the capacitors, if any are puffy or have black stuff on top, replace the motherboard.