Could very intermittent PSU issues be causing reboot?

x509

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I am a [H]ard|Gawd with over 2000 posts, but this is my first post in this forum. I'm wondering if by some chance my Corsair AX 850 power supply is the issue with random reboots of my new system. This PSU is about six years old and has run without any problems since I installed it. I'm wondering if some very intermittent issue is causing the problem here with my new system. I have no idea if power supplies have intermittent issues that cause a reboot, which is why I'm doing this post. And I need advice on tools to monitor my system to see if the PSU has voltage drops (?) that might indicate a problem.

I recently built a new system around an ASUS ROG X570 Strix-E motherboard and AMD 3900X CPU. After I built the system, I flashed the BIOS to the most recent version and changed the date and time but made no other changes to the BIOS. All was well, until a week after I finished the system, when it shut down suddenly, and would not start up again. When I pressed the Power button, the fans would spin for maybe 1 second, then stop spinning. I tore apart the system and rebuilt it. Before rebuilding it, I used a Thermaltake Dr. Power PSU tester and verified that all voltages were good. Following a suggestion I found in a thread about Gigabyte Aorus X570 motherboards, I also removed the CMOS backup battery and left it out overnight.

Once I rebuilt my system, it ran without issue from April 26 until last night, when it suddenly shut down again. This time I was able to reboot the system into Windows and resume work, and right now it's working fine. I've emailed ASUS support, which has replied promptly, but without any useful suggestions. With ASUS poor reputation for RMA, the last thing I want to do is send this board in for repair/replacement, especially now with the corona virus situation.

Thanks for answering this question.

 

warhol76

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Tracking down random restarts is the worst! I know this sounds dumb. But, the first thing I would tell you to do is check to be sure everything is plugged into the mobo tightly. I know you have said you unseated the CPU. A few years back, I thought I had a power supply issue causing random reboots and other weirdness. I ended up replacing my psu and the problem persisted. while in the case, I bumped the Graphics card and the whole thing shut down. It was at this point, that I realized the graphics card was not seated quite right. Taking it out and putting it back in solved all my problems! On the bright side, I upgraded to a nice modular power supply!

The short answer to your question is yes, it could be the PSU. It could be 50 other things. Have you noticed any pattern to it? does it happen when you are doing a certain thing or under load? Or, is it truly random? Good hunting.
 

kennyluu87

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As warhol76 stated. Random shutdown and restart can be almost anything. Even software errors or bad hardware drivers can cause these symptoms. The best way to figure out what the cause might be is wait it out and see if the system does the same thing. Then figure out what similarity both time that caused the system to reboot or shut down. Since you already tore the system down and put it back together this is the first step in identifying if there are any loose contacts. We can probably check that off. The next thing would be maybe rerun any drivers update. I would also run a bios update again just to make sure it's not software related. Then if none of these resolves it it's likely a component could be bad. If at anytime the system is shutting down or rebooting while you are on heavy loads I would check and make sure the psu has sufficient power as well.
 

x509

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Tracking down random restarts is the worst! I know this sounds dumb. But, the first thing I would tell you to do is check to be sure everything is plugged into the mobo tightly. I know you have said you unseated the CPU. A few years back, I thought I had a power supply issue causing random reboots and other weirdness. I ended up replacing my psu and the problem persisted. while in the case, I bumped the Graphics card and the whole thing shut down. It was at this point, that I realized the graphics card was not seated quite right. Taking it out and putting it back in solved all my problems! On the bright side, I upgraded to a nice modular power supply!

The short answer to your question is yes, it could be the PSU. It could be 50 other things. Have you noticed any pattern to it? does it happen when you are doing a certain thing or under load? Or, is it truly random? Good hunting.
I did not reseat the CPU or the heatsink. Butt when I did the teardown, I unplugged everything else from the motherboard, including the cards and the RAM.

My typical workloads haven't changed that much. I might be doing email (Outlook) or MS Word, but nothing heavy. One thing about this new system. Since I haven't made ANY changes to the BIOS yet, when there is heavy system loading the fans speed up for a few seconds. That happens only when I doing certain operations in Lightroom. Otherwise, the fans are silent. The only pattern I can observe is that these crashes never occur when the CPU fans are spinning loud.

Every time I have used a Power Supply calculator, the answer comes back that I need about 550 W. I have 850, and that was deliberate.
 
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x509

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As the OP, here is a history of my reboots. I keep a log of my system assembly process so I have good records:

Assembled system 4/17.
First shutdown 4/23. shutdown. When I pressed the power button, the fans would spin for 1-2 seconds, and the system would just start the boot process, then shut down and fans would stop.
Tore down and rebuilt system 4/26.
Next shutdown 5/7. This time the system rebooted automatically.
Next shutdown 5/10, about 5.55 pm. System rebooted automatically.
Next shutdown 5/11 (today) about 10.20 am. System rebooted automatically.

Shutdown is always sudden. No BSOD type entry in the system event logs.
 

warhol76

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When you say the system rebooted automatically, did it actually reboot back into the OS? Or did it shutdown and you had to reboot. Just want to make sure I am on the same page.
 

x509

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When you say the system rebooted automatically, did it actually reboot back into the OS? Or did it shutdown and you had to reboot. Just want to make sure I am on the same page.
warhol76 Good question. Thanks for asking. On the first shutdown, it just shut down. I couldn't actually reboot. After I rebuilt the system (and pulled the CMOS backup battery and left it out overnight), the system would automatically reboot back into Windows 10.

I have to say that my confidence in myself as a system builder is going way down. And this issue is making me look bad to my wife. :(

I had HW Monitor installed, but it doesn't help me see if there are hardware issues. So if there are any tools to monitor hardware that could help me pinpoint a source of hardware instability I'm open to suggestions. Same with smart ways to read the Windows event logs.
 

warhol76

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This type of thing will definitely make you go batty. Have you run any hardware diagnostics or tests?
 

x509

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This type of thing will definitely make you go batty. Have you run any hardware diagnostics or tests?
Funny you should ask. Two days ago I ran memtest86 overnight, 4 passes, and what-do-you-know, there was a 1 bit error that made 20 out of 48 tests fail. So I just got an RMA authorization from Crucial. I'm bummed that they won't cross-ship another memory kit, but it's a start.
Here is an interesting point. If you read my OP, you will see that the first time I had this problem, the system would not restart. After that the system automatically restarted after every crash. But when I first built this system I was using a 2 8 8 GB kit, which I ordered by mistake, thanks to Amazon's confusing search results. So I ordered the 2 x 16GB kit and returned the 2 x 8 GB kit. When I tore down and rebuilt my system after that first reboot issue, I was using the new RAM.

You can be sure that as soon as I get the replacement RAM, I will do at least 8 passes with memtest86. Then I will cross my fingers.
 

warhol76

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Wow, definitely hope that solves your problem! All the times I have run memtest, I have never gotten an error. Nonetheless, I will keep doing it; when I have problems. Good luck!
 

x509

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Wow, definitely hope that solves your problem! All the times I have run memtest, I have never gotten an error. Nonetheless, I will keep doing it; when I have problems. Good luck!
warhol76 I have the RMA, but I'm not planning to ship the memory back until next Tuesday. With Covid, I have to plan trips out carefully, so I'm stilling the same problem RAM. After having three reboots all in a row, the system has been stable for a week now. Go figure.

I just learned that I can do a "pre-paid" USP shipping label, so all I have to do is drop the box off at UPS and get a receipt. No forms to fill out, wait on line, etc. I know some people are going around without face masks and aren't social distancing, but I think they are just endangering themselves and others. Sadly some of them will get sick, badly sick and worse.
 

learners permit

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You didn't mention a cmos clear after the 2x8 modules change out. Incorrect timings could have precipitated the memory failure if it wasn't. They may not require rma after all anyway.
 

x509

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You didn't mention a cmos clear after the 2x8 modules change out. Incorrect timings could have precipitated the memory failure if it wasn't. They may not require rma after all anyway.
I did the RMA and just got the replacement RAM in today's mail, so I should have time tomorrow to install it. Fingers crossed. First thing I do is run memtest.
 

Nobu

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If it fails the same bit (or nearly the same), and the same tests, it may be the cpu or motherboard...but try reconnecting the 24pin and aux power connectors on the mb first, and if that doesn't help, then remove and reinstall the CPU.
 

x509

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If it fails the same bit (or nearly the same), and the same tests, it may be the cpu or motherboard...but try reconnecting the 24pin and aux power connectors on the mb first, and if that doesn't help, then remove and reinstall the CPU.
Thanks. This advice is appreciated.
 

Smoblikat

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Can you manually spin your case fans? If any of them feel tight/stuck a little, unplug them and see if that does it.
 

pitingres

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If the memory replacement doesn't work, something that you might try is verifying that the BIOS setting for Power Supply Idle Control is set to Typical Current Idle.
 
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kirbyrj

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How did the memory swap go? I've found that just about any issue with Ryzen is memory related. Relaxing a timing here, adjusting voltage there, and the system runs like a champ.

Much different than Intel where it's usually a matter of "will this processor run at this speed with this voltage." If yes, then you get a working system. If no, then it reboots.
 

JustinC

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The only easy way of finding out whether the power supply is the problem or not, get another power supply kit, and check if the issue persists.
If the issue persists then it means that the power supply is ok.
One thing you can check is if everything is seated properly and all the wires are connected tightly. Loosely connected cables may be causing the intermittent reboot issues.
 

x509

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How did the memory swap go? I've found that just about any issue with Ryzen is memory related. Relaxing a timing here, adjusting voltage there, and the system runs like a champ.

Much different than Intel where it's usually a matter of "will this processor run at this speed with this voltage." If yes, then you get a working system. If no, then it reboots.
So far so good, a month after installing the new RAM. I am one happy camper right now. Not a single sudden reboot.

To be safe, I'm going to run this system for a few more weeks, then I will dive in and tweak. And possibly replace the AMD stock cooler with something like that high-end Noctua (forget the model number).

What this means is, the PSU is indeed good, which is a relief. My PSU tester showed all good readings. Of course I did check all cables for proper insertion at the PSU end and at the board end.

To respond to some other questions in this thread no BSOD or other error message from Windows. Fans all spin freely. Aside from setting date and time, I have not touched BIOS, the idea being to run the system at all stock settings for a sort of "burn in."

I would have replied sooner, but my "better half" has found lots of around-the-house projects for me to do while we are cooped up inside the house. We live in a state which is being very slow to ease up on Covid precautions.
 
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