MinisForum Mini Computer x400 turns itself off randomly

winver 22h2 19045.5247

I have a mini pc from Minis Forum. It is model x400 running Windows 11 Pro. Recently it has been losing power as in it just turns itself off with no proper shutdown. Windows event viewer shows an unexpected shutdown and that is it. I performed the following...

1. Replaced the CPU. It has an AMD Ryzen 7 5700G processor.
2. Replaced the power supply. Voltage is 19v 6.32A 120w.
3. Replaced the nvme storage.
4. Performed a fresh install of Windows 11 Pro. I wiped the nvme completely and then performed the install.
5. BIOS is up to date.
6. Cleaned and applied new thermal paste. Temps are averaging 45-55 Celsius on idle.
7. RAM is 64GB x2 32GB sticks. I swapped them, reseeded them and tried one at a time. Even ran RAMTest without issues. I have not completely swapped out the RAM for another RAM because I don't have any on hand.
8. The computer will stay on all day long with no issues when sitting in BIOS. So the problem seems to only occur when loaded into Windows. The computer came with Windows 11.
9. Before the current issue, the computer wouldn't POST at all because the CPU was failing. AMD replaced it under warranty and I have that new CPU installed. But the computer now randomly loses power as opposed to with the defective CPU which wasn't allowing POST at all.
10. I am currently testing to see if the computer loses power while loaded into Windows 11 installed by USB. I am just leaving it there after it boots into the installer just to see if anything happens.
11. I've checked the pins of the CPU for any damage and there is none. I've done the same with the motherboard and nothing looks out of the ordinary.
12. I am currently testing a fresh install of Windows 11 Pro on a 2.5 SSD instead of using the nvme slot to see if maybe the nvme slot is bad. Will update.
13. The computer has a m.2 2242 slot, a 2280 slot and a 2.5 SSD plug. All my tests have been using the 2280 slot. I am waiting on a 2242 128gb and a 2.5 SSD drive in the mail to rule out a problem with the 2280 slot.
14. I've also removed all connected devices to the computer. All I have connected to it is the power supply, a USB keyboard and an HDMI computer monitor that has touch capability but I have removed that from the equation an am just using the HDMI port rather than the USB port to enable touch.
15. The computer has always been plugged up to a UPS. However, for testing I have used other plugs and issue continues.
16. At this point I am thinking a motherboard issue. Unfortunately the model is discontinued and if I were to find a replacement I would have to either get lucky and find the motherboard gutted somewhere on the web or I can still find the complete computer new/used on ebay but at a hefty $400+ that I don't want to go that route yet.

At this point I am exhausting my resources and looking for collective help. Maybe I am missing something or someone could suggest an idea I haven't thought of yet. Any help would be greatly appreciated!

JDubbedN said:

Temps are averaging 45-55 Celsius on idle.

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But what are temps under load?

glasskuter said:

But what are temps under load?

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How would you like me to test it? Using a stress test software? I've just let the computer sit there while idle sitting in Windows and it turns off eventually usually within an hour.

JDubbedN said:

10. I am currently testing to see if the computer loses power while loaded into Windows 11 installed by USB. I am just leaving it there after it boots into the installer just to see if anything happens.

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I have confirmed that the computer will not turn off when sitting in the Windows 11 installer window booted from a USB drive. That is also consistent with the BIOS. I can leave the computer in the BIOS for hours and the problem will not present itself. So far the only way the computer will randomly lose power is if it is loaded into Windows. This happens on a fresh Windows 11 Pro install.

JDubbedN said:

This happens on a fresh Windows 11 Pro install.

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just for testing purposes.. have you tried win 10? really curious to know

dacrone said:

just for testing purposes.. have you tried win 10? really curious to know

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I will install Windows 10 and report back.

dacrone said:

just for testing purposes.. have you tried win 10? really curious to know

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Windows 10 installed and I got to where it said "Getting things ready" and then the computer turned off. I tried to turn it back on and the computer's power button would light up for a second then turn off. I had to unplug the power, hold down the power button for 10 seconds to get the computer to boot back up. When it entered Windows 10 and I saw the desktop, windows notification was saying "installing display drivers" and then the computer lost power again. Now, whatever I seem to do, when I turn the computer back on the power button lights up for a second and then the computer turns off. Unplugging the power and holding the power button for 10 seconds doesn't seem to work now. I have tried turning the computer on with nothing but the power plugged in and still won't turn on. I am leaving everything unplugged and going to give the computer some time to rest to see if it'll work again later. But it would seem Windows 10 is worse than Windows 11.

that definitely cannot be an OS issue. have you tried changing the power cable (i would assume so since you swapped PSU)? have you checked the pin connector on the MB to make sure there is nothing offset/bend in the socket (the (typically) 20+4 pin?

dacrone said:

that definitely cannot be an OS issue. have you tried changing the power cable (i would assume so since you swapped PSU)? have you checked the pin connector on the MB to make sure there is nothing offset/bend in the socket (the (typically) 20+4 pin?

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I was able to turn the computer on and it stays on after letting it sit for a couple minutes. I am letting it sit at the Windows 10 desktop to see how long it lasts just sitting there before it powers off. This is a mini computer which means it doesn't have traditional motherboard pins. It is like a laptop motherboard. The power port is soldered onto the motherboard. The power supply is a power brick like a laptop power supply is.

I have tried changing out the power supply/brick for another and problem persists. I am using a 19v 6.32amp power supply from here Amazon.com

"mini forums motherboard" doesn't bring up any directly corresponding search results. can you supply a MB part/model number?

@dacrone The computer lasted about 10 minutes before it shutdown. I was actually able to witness it this time and all I saw was the computer monitor going black and the power button on the computer turning off. Nothing that tells me why it turned off though.

dacrone said:

"mini forums motherboard" doesn't bring up any directly corresponding search results. can you supply a MB part/model number?

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The only model number I see on the motherboard is ATB15_MB_v22_20210223A. The computer name is Minis Forum EliteMini x400.

dacrone said:

"mini forums motherboard" doesn't bring up any directly corresponding search results. can you supply a MB part/model number?

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I was able to find the website link to the product.

minisforum

JDubbedN said:

The only model number I see on the motherboard is ATB15_MB_v22_20210223A. The computer name is Minis Forum EliteMini x400.

I was able to find the website link to the product.

minisforum

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you can try the steps outlined here... its not the same model, but possible solution:

.https://www.reddit.com/r/MiniPCs/comments/1ce2fig/minis_forum_hx99g_powers_up_but_stuck_at_black/

EDIT:
this pertains to your model:
.https://www.youtube.com/watch?v=Ldk_Jaa-dh0

have you checked the reliability monitor.
control panel > security and maintenance > maintenance > reliability monitor.

see if any errors are listed there.
best of luck, Steve ..

dacrone said:

you can try the steps outlined here... its not the same model, but possible solution:

.https://www.reddit.com/r/MiniPCs/comments/1ce2fig/minis_forum_hx99g_powers_up_but_stuck_at_black/

EDIT:
this pertains to your model:
.https://www.youtube.com/watch?v=Ldk_Jaa-dh0

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That youtube video with Sorin is pretty crafty. Good find. It is the same computer however in his situation the computer is not even booting. My computer is turning on, POSTING and booting into the OS but then some time later the computer turns off and then it takes some time for it to turn back on I assume because the electricity needs to fully be removed from it. Could be a bad chip, could be a short somewhere. That is way over my head. I won't be able to do what Sorin did in that youtube video. But it looks like that video was very recent, maybe a week ago which is interesting timing. Maybe I can reach out to Sorin and see if he's interested in taking on my challenge since he just worked with the same computer.

I can try the reset button on the front of the computer and follow the reddit post you provided. I am also going to try a different monitor. Maybe the HDMI port is causing a short or maybe a USB port is causing a short. Since I don't have the electrical knowledge to troubleshoot like Sorin did in that youtube video I can only trial and error until something gives. Any ideas let me know. I'll report back additional findings as I come across them.

XxXxX said:

have you checked the reliability monitor.
control panel > security and maintenance > maintenance > reliability monitor.

see if any errors are listed there.
best of luck, Steve ..

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I'll check the logs and see if I can find anything.

JDubbedN said:

2. Replaced the power supply. Voltage is 19v 6.32A 120w.

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JDubbedN said:

I can try the reset button on the front of the computer and follow the reddit post you provided. I am also going to try a different monitor. Maybe the HDMI port is causing a short or maybe a USB port is causing a short. Since I don't have the electrical knowledge to troubleshoot like Sorin did in that youtube video I can only trial and error until something gives. Any ideas let me know. I'll report back additional findings as I come across them.

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gotcha. i reread your original post and i misinterpreted it. i was thinking you replaced the psu, which sounds like it is soldered on. yeah i would definitely check the psu and all leads around it to make sure nothing is damaged on the MB.

dacrone said:

gotcha. i reread your original post and i misinterpreted it. i was thinking you replaced the psu, which sounds like it is soldered on. yeah i would definitely check the psu and all leads around it to make sure nothing is damaged on the MB.

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I just booted up Windows 10 again. After watching that youtube video Sorin mentioned USB ports and so I thought I would plug and unplug devices while the computer is on. First time while booted into Windows 10 I plugged in a USB mouse receiver and BAM computer turned off. I did it a couple times more and sometimes plugging/unplugging a USB device causes the computer to turn off and sometimes it doesn't. But that sounds like it is related to the chip Sorin removed from the motherboard which he said was in charge of providing power to the USB ports. There isn't any way for me to do the work Sorin did. I just don't have the knowledge. Is there someone that you know of here in the forums that knows how to do what Sorin can do? Maybe I can ship it off to that person and they can give it a go.

Looking at the video I found it interesting that there was very little or no thermal paste on the CPU. I wonder if they did the same on your computer and the CPU is getting hot and shutting off the computer.

Winuser said:

Looking at the video I found it interesting that there was very little or no thermal paste on the CPU. I wonder if they did the same on your computer and the CPU is getting hot and shutting off the computer.

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I have replaced the thermal paste several times while diagnosing the cpu. I apply new thermal paste every time the heat sink is removed. And the temps confirm it is staying cool.