Motherboard showing no sign of power

Muz294

Prominent
Mar 20, 2017
4
0
510
Got a new motherboard and CPU for my sister recently. At first I was getting the green LED on the motherboard but the system would not turn on at all. I reset the CMOS and it started working again, installed windows and noticed the GPU wasn't being detected at all.

So I fiddled around with it, re-seated it, disconnected and reconnected the PCI-e power connectors and still got nothing. I then replaced the GPU with an older one and it worked flawlessly. Put the old one back in and now I'm getting absolutely ZERO sign of life on the motherboard.

Nothing will turn on, not even the green LED on the motherboard. I've replaced the PSU and still nothing, checked everything is plugged in correctly and even changed the cable connecting the PSU to the mains. It's driving me nuts. Any help would be appreciated.

Cheers
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Specs:
MOBO: Asus PRIME B250M-A
CPU: i5 7500
GPU: Radeon R9 270X
PSU: Corsair CX 430M
 
Solution
So it has to be some kind of hardware problem with motherboard. It is not necessarily dead, maybe it's some kind of surge protection kicked in. I guess you should contact Asus customer support and ask them if they know how to put it back to life. Or ask replacement board if they can't help otherwise.
I wonder how it happened that you found out GPU is not working after Windows install? If you had connected monitor to GPU (as you should) you would get no display if GPU is not working.

Now for the problem: remove GPU, connect monitor to motherboard and run the machine. It would be very strange if it would not work.

Another thing to mention is, for r9 270x recommended power supply is 500 W.
 

Muz294

Prominent
Mar 20, 2017
4
0
510
Thanks for your fast reply. I had the display plugged in via the motherboard rather than the GPU as I couldn't get a picture from the GPU in the first place.

I've already unplugged everything except the CPU + RAM and still can't get the motherboard to do a thing. Still no green LED either.

The R9 270X was already running on the 430 W power supply for almost two years with no issues.

 


With both PSU? That's weird. If that happened from the start, I would consider faulty motherboard. Or PSU, but that works, right? However, motherboard worked before that GPU swap. And I don't think you could fry it just by swapping GPU (unless doing that on powered machine :) ).
I guess you did another cmos reset after removing GPU?
 

Muz294

Prominent
Mar 20, 2017
4
0
510
Yep, same outcome with two different PSUs. The other is 750 W and has absolutely nothing wrong with it. I'm beginning to think it's a faulty motherboard too, however I had it working absolutely perfectly (besides the GPU not being detected) before I swapped the GPU over. I have reset the CMOS multiple times and still no change :/
Just to note I always remove the power cable before messing with components so I doubt it would have been fried by swapping the GPU.
 
So it has to be some kind of hardware problem with motherboard. It is not necessarily dead, maybe it's some kind of surge protection kicked in. I guess you should contact Asus customer support and ask them if they know how to put it back to life. Or ask replacement board if they can't help otherwise.
 
Solution