[SOLVED] PC wont turn on anymore, suspect it's the PSU

[AnonymousAlvin]

I built a small form factor desktop in 2019, the specs are listed below:

• CPU: Ryzen 3700x
• CPU Cooler: Cryorig C7
• GPU: Nvidia RTX 2070 Super
• PSU: Seasonic Focus SGX Gold 650
• RAM: Ripjaws 32GB DDR4 3600MHz
• Motherboard: Aorus X570 I Pro WiFi
• Case: SilverStone Little Raven RVZ02B

After a couple months of use, my PSU seemed to have broken from an unknown reason. I still had a CX850m from my previous build I used to temporarily fix my computer until I could get a replacement. I procrastinated horribly with replacing the PSU, until March of this year, and got a replacement unit. However, again after a couple months of use, it seems my PSU might have broken again just now as my desktop wont turn on anymore.

I suspect it is something wrong with the PSU, perhaps too little wattage, as I didn't have any issues with my CX850m for the long time I was using that PSU instead, the only difference being the higher wattage and that my case was open with the PSU sticking out as it was a ATX and not SFX, so it wouldn't fit in my case. I just now ordered a CoolerMaster V850 SFX as I hope this will fix my problem and I don't know if I can get another replacement unit for my Seasonic PSU.

I just performed a paperclip test with the Seasonic PSU, and it seemed like the fan just twitched as I plugged it in, but it doesn't actually spin up. I also heard a sort of "ping" noise. When I power off the PSU after the paperclip test, after a couple of seconds the fan gets a short jolt/push, before it spins to a halt.

Can I assume here that the PSU is the culprit, and getting the CoolerMaster V850 SFX instead will solve my problem? It makes sense to me as it seems to only last a couple of months before it broke the first and second time. What could be other causes for my PSU to suddenly break in a small form factor build?

Any help would be greatly appreciated.

 

[AnonymousAlvin]

I made a video recording of me doing the PSU test, probably more helpful: https://streamable.com/wx0ao0

 

[geofelt]

The paper clip test is essentially useless.
It can only confirm a dead psu.
It can not test for proper operation

Seasonic Gold units may never turn the fan on at all; that is normal.

Your setup should run with even 550w.
http://www.realhardtechx.com/index_archivos/Page362.htm

Your Seasonic Focus SGX 650w is of excellent quality and has a 10 year warranty.
Since it is modular, check that both ends of the cables are inserted well.
The fact that a different PSU seems to work is, indeed an indicator that the Seasonic psu is faulty.
Contact Seasonic for a RMA replacement.

 

[AnonymousAlvin]

The paper clip test is essentially useless.
It can only confirm a dead psu.
It can not test for proper operation

Seasonic Gold units may never turn the fan on at all; that is normal.

Your setup should run with even 550w.
http://www.realhardtechx.com/index_archivos/Page362.htm

Your Seasonic Focus SGX 650w is of excellent quality and has a 10 year warranty.
Since it is modular, check that both ends of the cables are inserted well.
The fact that a different PSU seems to work is, indeed an indicator that the Seasonic psu is faulty.
Contact Seasonic for a RMA replacement.

Thank you for the reply. I'm very confused though how it could have broken again, and if they will even provide me with a new PSU at all since I already got a replacement unit in March.

I think you may have misinterpreted the timeline of my original post. I built this desktop in July of 2019. My PSU broke twice, once back in November of 2019 after 3-4 months of use, after which I used a different PSU up until March of 2021, which is when I finally decided to get a replacement for my Seasonic PSU. Now, the replacement Seasonic PSU broke but I don't have the other PSU anymore to confirm it is actually the PSU that is faulty.

It seems weird to me that the other PSU that I used for ~1.5 years didn't fail on me at all, and that this one seems to break after a couple months. I suspect it could be due to temperatures. Is if possible for high CPU temperatures to cause a PSU to break by any chance?

 

[geofelt]

Who is "they" that supplied the replacement.
If it was seasonic, I would trust them.
A store, not so much.
They might have sent you another defective return.

I doubt high temperatures could cause a quality psu to fail.
First, you have plenty of power so the psu is not running at capacity.
If the psu gets hot, that is when the fan starts spinning.
If the fan were faulty, I suppose that could cause a problem.

 

[AnonymousAlvin]

Who is "they" that supplied the replacement.
If it was seasonic, I would trust them.

I requested the RMA through Seasonic directly, not through the store I bought it from. But I was instructed to send it to a computer repair facility in Germany which didn't carry Seasonic's name, but seemed to be a authorized Seaconic repair facility. I received a new unit still wrapped in plastic from them.

I doubt high temperatures could cause a quality psu to fail.
First, you have plenty of power so the psu is not running at capacity.
If the psu gets hot, that is when the fan starts spinning.
If the fan were faulty, I suppose that could cause a problem.

Mhh, I guess I'll have to troubleshoot a bit more then. I'll request another RMA then, and see if I could further see what could cause the issue.

Are there any other causes that come to mind as to why a PSU could fail after 3 months? Or did I just get unlucky these two times?

 

[geofelt]

Unlucky twice seems a bit far fetched.
But, I have no other ideas.

 

[AnonymousAlvin]

Unlucky twice seems a bit far fetched.
But, I have no other ideas.

Thanks for your help/advice. I've got a friend coming over tomorrow with a multimeter and extra PSU to diagnose the problem together.

 

[AnonymousAlvin]

Well, somehow my friend was able to fix it.

1. We first used the multimeter to check if the PSU was outputting the correct voltage to the motherboard. There seemed to be no problem there, so my friend was confused as it would seem the PSU was still working.
2. We started taking out certain components. We tried putting only a single RAM stick in in different slots. We removed the GPU. None of these made a difference.
3. We checked if the power button was still working with the multimeter. Again, it seemed to be working fine.
4. Now we decide to use the other PSU he brought. As I had hoped, the computer booted fine using this PSU.
5. We assume this meant the Seasonic PSU was indeed broken, but my friend insisted on plugging it back in and testing it again, as he said nothing seemed to be wrong with it from testing with the multimeter. Alas, the computer booted with all the original parts, when it was not booting like this before we started diagnosing the computer.

After further investigating, my friend noticed that there was carbon on the extension cord inside the case for the PSU. The case comes with an extension cord built into it, as the PSU is located in the front/bottom of the case, and the extension cord routes a plug to the back of the case. This cable seemed to have been damaged at some point, but we don't know how or when.

We suspect that a defective power cord caused static to build up in the motherboard (or maybe PSU), preventing it from booting. Putting in another PSU solves the issue. So it may have been that when I first RMAed my first Seasonic PSU, it wasn't actually broken, but they didn't check if it was actually damaged, but just sent a new unit assuming it was dead.

The reason the backup PSU that I used for 1.5 years didn't die on me is because I wasn't using the case's extension cord. I only started using it again in March 2021, when I got the replacement PSU.

Anyway, now I'm writing this from my desktop without the same parts. I'm still confused about what exactly was the problem, but I'm happy it's fixed. Need to get a new extension cord for my case though.

Not sure if this will ever be relevant to people in the future, but thought I'd write what we did to solve it. It couldn't hurt.