Question Motherboard dead?

[dave1310]

I have a homebuilt, Asus M5A99X EVO R2.0 motherboard, AMD Phenom 4 core processor, 8gB Corsair Vengance memory 1600gHz 9-9-9-24 and an Asus video board (inexpensive but I can't find the box and there is no description on the card. Nvidia though). I was using a Corsair VX550W power supply.Unit has run superbly for over 2 years.
Last week I clicked a key to wake it up and it got to the desktop and then it quit as though the plug had been pulled. No lights, no nothing! thinking the power supply had died, I replaced it. Nothing. Not a sound or a light. Humm! It was a slightly older supply from another build so I thought it was bad and I had just forgotten. So, I pulled out a brand new Antec HGC-620M I got for another build and installed it. Hooked up the periphials and turned it on. booted fine and I went "Yeah, that's the ticket!". And it was, for about 20 minutes. Then it died, again as though the wall plug had been pulled. Attempts to restart did nothing. no fans no boot, totally silent. There is a single green light on which extinguishes when the PS switch is turned off.
I thought sure I had it when it booted and ran with the new PS. apparently not.
Thoughts? What am I missing here?

 

[Dark Lord of Tech]

I had a similar situation with an Asrock 990FX Extreme9 years ago and it was a faulty board.

 

[dave1310]

First, sorry for delay in response but it seems like I've been dicking around with this computer for a lot longer than 3 weeks.
I agree and have ordered another M5A99X EVO R2.0 MB. The plan is to move everything over and see how it goes. I'd think that with everything being the same except the MB serial #, there should be no problem with Windows. Do you agree?