PC flashes half a second when turning it on and then shuts down HELP!

[GameTime007]

So, I just built a new PC, but when I came back from getting my USB with Windows, after I changed the CPU Fan profile in the BIOS, I discovered the PC somehow was turned off. But when I turned it on, nothing happened. Onlz if I press the power button for like 1-2seconds the RGB flashes, the fans spin and the whole thing turn black again half a second later. If i keep my finger on the power button this keeps happening and I can hear a quiet “zapp” in the PSU. I already reseated all the cables, changed the PSU wall cable, tried differen wall outlets et cetera. Whal shall I do? Does anyone know what might be happening? I have a slight suspicion with that PSU, but its brand new and worked just fine 5 minutes ago.

 

Specs:

i7 7820k

Asus Strix x299-XE

32GB TridentZ RGB (3200)

512GB 960Pro

Corsair RM850x with CableMod cables

[GameTime007]

Oh, and I might have a spare power supply somewhere, should I try that??

[Crunchy Dragon]

Usually if you hear any noise like that from the PSU and the computer won't start, you may have a dead CPU and/or motherboard on your hands.

[GameTime007]

Oh please no! And why would that be? Could the PSU have somehow fried the whole thing??

[Ghostsquidy]

Try the spare power supply first as the zapping sound might be a dead PSU. If that doesn't work then I would try shorting power button pins on the motherboard that connect to the power button with a screwdriver just in case the power button is weird and not connecting right

[light-v]

Just now, GameTime007 said:

Oh please no! And why would that be? Could the PSU have somehow fried the whole thing??

It can happen but I don't think that a RM850x would, good PSUs usually die alone. Since your have a spare PSU you should give it a try

[glenalz81]

9 minutes ago, GameTime007 said:

So, I just built a new PC, but when I came back from getting my USB with Windows, after I changed the CPU Fan profile in the BIOS, I discovered the PC somehow was turned off. But when I turned it on, nothing happened. Onlz if I press the power button for like 1-2seconds the RGB flashes, the fans spin and the whole thing turn black again half a second later. If i keep my finger on the power button this keeps happening and I can hear a quiet “zapp” in the PSU. I already reseated all the cables, changed the PSU wall cable, tried differen wall outlets et cetera. Whal shall I do? Does anyone know what might be happening? I have a slight suspicion with that PSU, but its brand new and worked just fine 5 minutes ago.

 

Specs:

i7 7820k

Asus Strix x299-XE

32GB TridentZ RGB (3200)

512GB 960Pro

Corsair RM850x with CableMod cables

I've seen this even be down to a dodgy fan molex connector.

 

3 minutes ago, Ghostsquidy said:

Try the spare power supply first as the zapping sound might be a dead PSU. If that doesn't work then I would try shorting power button pins on the motherboard that connect to the power button with a screwdriver just in case the power button is weird and not connecting right

Agreed here, also try disconnecting anything that's not necessary. 

[GameTime007]

Is there a possibility the “spare PSU” could be fried? Because its from another PC

[Ghostsquidy]

Try using any PSU that you KNOW works 100% and then use only the MOBO, PSU, 1 ram stick and CPU (the bare minimum to post) and then gradually add back parts till the problem happens again. Then you can figure out what the problem is. Do this outside of a case so it's easier to look for any problems that you can see and for convenience

[GameTime007]

Soo, I tested it. I did the exact same thing.

CRAP

Guess I have a dead MB in my hands?

[GameTime007]

 

15 minutes ago, Ghostsquidy said:

Try using any PSU that you KNOW works 100% and then use only the MOBO, PSU, 1 ram stick and CPU (the bare minimum to post) and then gradually add back parts till the problem happens again. Then you can figure out what the problem is. Do this outside of a case so it's easier to look for any problems that you can see and for convenience

It had worked just fine. Should I like, RMA it back?? To Amazon or to Asus, Corsair etc, since I still dont really kow whats dead and what caused it all. It was originally inteded as a birthday gift on April 13th. Guess thats not gonna happen..

[GameTime007]

Gonna take it out of the case now and try testing it on the MoBo box. Ill try to eliminate every factor that might lead to this. Will also inspect the CPU and socket

[GameTime007]

I also noticed a red LED at the top left of the Motherboard. In the manual its labeled “PLED5300”. I dont think it was lit before..

[GameTime007]

Sooooo, apparently it was some BIOS related error. We put the MoBo on its Box and performed a CMOS clear with battery removal. And, we got postcodes. I have no idea what the problem was, but it seems to have resolved without any RMAs. Thanks for the support and tips. This has been an absolute roller coaster!