Question Help Identify faulty part.

[Tomjoppe28]

Hey all,

I recently built a computer for a friend, the day we put it together it worked absolutely fine. The day after it did too for around 4 hours. While playing Forza horizon 4 suddenly the computer completely shut off. When we tried turning it on it would flash led lights and spin the fans for about 1/2 a second and then shut off. After shutting off it wouldn't turn back on unless you kept it unplugged for a minute or more. After that, it would do the same 1/2 second startup thing. Eventually, I took the PSU out and tested it with the paperclip method and nothing else connected. It would again also turn on for half a second on its own and then would shut off. Eventually, I tried taking the whole motherboard out and running it out of the case because when I was plugging in cables into the motherboard I noticed that when I pressed down on the 24 pin connector on the motherboard the computer would turn on and off, I thought this could be because of a short to the case so I took the motherboard out and suddenly the computer booted up normally. I gaffer taped behind the motherboard just to make sure the 24 pin connector wasn't shorting out on the case and put everything back in. Long and behold everything worked fine. But then again a few hours later it turned off by itself again and also would do the 1/2 second startup thing and shut down again. So I'm thinking it's most likely the PSU since it exhibited the same problem out of the case but I'm also skeptical it could be the Motherboard. Since I want to RMA the parts that are not working I want to make sure the I return the correct part.

The specs of the computer are:
Ryzen 3600
Ballistix DDR4 Sport LT 2x8GB 3200
Asrock B450M PRO4
Cooler Master MWE Gold 650 Full Modular PSU
Asrock Radeon RX 5700 Challenger D 8G OC
Crucial P1 1TB M.2 SSD
Lian Li LANCOOL ONE
Cooler Master Hyper 212 black edition
PATRIOT MEMORY P200 2.5" 1000 GB SATA III

All help is appreciated!

Thanks and regards,

Tom

 

[R_1]

play a game of swapsies with your PSU. replace the PSU with another for testing and see what is what. if the behavior persists the motherboard is the most likely issue. if the new PSU clears up the issue, well, there you go.

 

[Greatli]

Sounds like you already figured out it was the psu with the first paper clip test.

 

[Tomjoppe28]

play a game of swapsies with your PSU. replace the PSU with another for testing and see what is what. if the behavior persists the motherboard is the most likely issue. if the new PSU clears up the issue, well, there you go.

I would like to be able to but don’t have a psu to test with.

 

[Tomjoppe28]

Sounds like you already figured out it was the psu with the first paper clip test.

Yeah thats what I thought but I’m still a bit skeptical.

 

[Paperdoc]

In your assembly process, did you check and verify for sure the placement of all the mobo stand-offs? These are usually little brass pieces with a threaded shaft in one end and a threaded hole in the other. Often they are pre-installed in a case, but it is possible they are in the wrong location. Ideally there ought to be one under each mounting hole in the mobo - and most mobos have nine, in three rows of three. But MOST IMPORTANTLY there should NEVER be a stand-off under the mobo where there is NOT a matching mounting hole in the board. Such mis-location can cause a short circuit to Ground from a mobo back-side trace, and this can appear to occur randomly, like when things heat up and shift, or when you flex the mobo.

I you are not sure about this, you need to shut down, disconnect power and open the case. Probably you would need to remove the mobo from the case and examine carefully where all the stand-offs are currently screwed into the case back plate. Compare those to the mobo mounting holes and make sure they all match exactly. If necessary, remove any in the wrong spots and re-install correctly. Then replace the mobo, checking carefully that ALL of them match up with mobo mounting holes, then install the screws.

If you look closely at the none mounting holes you will see small metal "fingers" in a star shape around them usually. The intent is that the mobo will be Grounded by the screws through the mounting holes into the stand-offs ONLY at these spots (and also via the main power supply cabling) and nowhere else.

 

[Tomjoppe28]

In your assembly process, did you check and verify for sure the placement of all the mobo stand-offs? These are usually little brass pieces with a threaded shaft in one end and a threaded hole in the other. Often they are pre-installed in a case, but it is possible they are in the wrong location. Ideally there ought to be one under each mounting hole in the mobo - and most mobos have nine, in three rows of three. But MOST IMPORTANTLY there should NEVER be a stand-off under the mobo where there is NOT a matching mounting hole in the board. Such mis-location can cause a short circuit to Ground from a mobo back-side trace, and this can appear to occur randomly, like when things heat up and shift, or when you flex the mobo.

I you are not sure about this, you need to shut down, disconnect power and open the case. Probably you would need to remove the mobo from the case and examine carefully where all the stand-offs are currently screwed into the case back plate. Compare those to the mobo mounting holes and make sure they all match exactly. If necessary, remove any in the wrong spots and re-install correctly. Then replace the mobo, checking carefully that ALL of them match up with mobo mounting holes, then install the screws.

If you look closely at the none mounting holes you will see small metal "fingers" in a star shape around them usually. The intent is that the mobo will be Grounded by the screws through the mounting holes into the stand-offs ONLY at these spots (and also via the main power supply cabling) and nowhere else.

The computer is currently at my friends place but unless the factory installed standoffs are in the wrong place it isn’t wrong since I installed the standoffs by holding the mobo above the case and seeing where standoffs were missing. But I will check next time I have the computers in my hand. What do you mean with replace, replace as in replace or as in placing the motherboard in the case again? Thanks for all the help everyone!

 

[Paperdoc]

Replace as in re-install, since I suggested you take it out for this. NOT get a new mobo!

 

[Tomjoppe28]

Replace as in re-install, since I suggested you take it out for this. NOT get a new mobo!

Great thats what I thought, thanks!

 

[Tomjoppe28]

I also just read the reviews about the power supply, a few of them said the cables are quite fragile and that they broke within 3 weeks. So it could have been a broken cable, by now the PSU has been sent back for RMA. We'll see if exchanging the PSU fixes the problems.