Question PC auto turn off and further impossible to switch on

[alex4998]

I’ve made 2 almost identical PC builds in 2023 (the difference is in GPU only):

1) ASUS ROG STRIX B760-F GAMING WIFI;

2) Intel Core i5-13400;

3) WD_BLACK SN770 NVMe SSD 2 TB High-Performance NVMe SSD, Gaming, PCIe Gen4, M.2 2280;

4) Corsair Vengeance RGB 32GB DDR5 RAM with 2 Modules (2x16GB) and Speed 5200 for Desktop (CMH32GX5M2B5200C40);

5) Corsair RM850x Shift 850W Full Modular 80 Plus Gold PC PSU;

6) Noctua NH-U12S chromax.black;

7) GPU Asus GeForce RTX 4070 12GB GDDR6X ProArt OC Edition Graphics Card and Gigabyte GeForce RTX 4070 12GB GDDR6X Windforce OC

8) CORSAIR iCUE 4000X RGB Mid-Tower ATX;

9) Windows 11 Pro; all updates installed.

10) ESET Smart Security Premium is on board.

Starting from December 2024 both PC started sporadically auto turn off during load or without load. After such auto turn off you cannot switch PC on. Only after some time it’s possible to switch on PC again.

What already was done:

Q-LED was showing problem with Video Card and Boot on both PCs. Both BIOS and Intel ME were updated, so now Q-LED is not showing any problem with any of the components.***

In addition, CPU on both systems was tested using Intel® Processor Diagnostic Tool - no problems were revealed. https://www.intel.com/content/www/us/en/download/15951/intel-processor-diagnostic-tool.html

BUT the “auto turn off and further impossible to switch on” problem still persists.

Any idea what shall be done further to eliminate the problem?

Thank you in advance.

***

BIOS and Intel ME update info

ROG STRIX B760-F GAMING WIFI | Gaming motherboards｜ROG - Republic of Gamers｜ROG Global

Get more FPS with the ROG Strix B760-F, thanks to its hyperfast DDR5 support and best-in-class power solution for Intel 13th Gen processors.

rog.asus.com

Version 1805

12.8 MB 2024/11/12

"1. Updated with Intel microcode 0x12B to address elevated voltage requests during idle or light activity, further mitigating Vmin Shift instability issues.
2. The option to disable C1E in the BIOS has been removed to ensure it remains enabled, reducing processor stress and maintaining stability per Intel's recommendation.

Before running the USB BIOS Flashback tool, please rename the BIOS file (SB760F.CAP) using BIOSRenamer.
Updating this BIOS will simultaneously update the corresponding Intel ME to version 16.1.32.2473v3. Please note after you update this BIOS, the ME version remains the updated one even if you roll back to an older BIOS later. "

 

[SkyNetRising]

both PC started sporadically auto turn off during load or without load.
After such auto turn off you cannot switch PC on. Only after some time it’s possible to switch on PC again.

Those are symptoms of PSU protections kicking in.
Reduce GPU power target. Use MSI afterburner.

Check your system for cryptomalware infections. Use Malwarebytes Antimalware.

 

[alex4998]

Thank you for your prompt reply.

Re MSI afterburner - I tried to launch the system without GPU - the same problem.

Re Malwarebytes Antimalware - will try it.

The problem is I cannot start system, have to wait couple of hours. Any idea how to overcome it? PSU is quite powerful, as far as I understand.

 

[Roland Of Gilead]

Well the PSU is very a very good one. That doesn't mean that it's not faulty. But having two of the same, and both going faulty simultaneously, is very odd and probably unlikely.

Did you clear CMOS after the bios upgrade? This might help.

Your GPU isn't a power hungry card. It consumes only 200w at full load. It's very efficient.

You might check all internal cabling, and consider replacing some as if only one of them has a short then PSU overprotection's might kick in as suggested above.

 

[SkyNetRising]

I tried to launch the system without GPU - the same problem.

Check cpu and gpu temperatures.

The problem is I cannot start system, have to wait couple of hours. Any idea how to overcome it?

Disconnect power cable from PSU to wall.
PSU protection status should reset.

Also check PSU fan. It may have failed and PSU is overheating.
That can also cause PSU shutdown.

 

[alex4998]

Roland Of Gilead​

Thank you for your input!

CMOS was cleared.

I'll check the cables. Maybe it's LED of the housing and/or additional fans causes problem? I'll try to isolate them.

 

[alex4998]

Update of the situation and measures, which were taken:

1) I have checked the PSUs (Corsair RM850x Shift 850W Full Modular 80 Plus Gold PC PSU) on 2 "PCs with problem" - they work fine.
How I've checked them:
a) I connected my 3rd PC to PSUs of 2 "PCs with problem". This 3rd PC was working fine with both PSUs, without any issues.
b) However, when I connected 2 "PCs with problem" to a 3rd PC's PSU (1000W), none of them worked (2 PCs didn't turn on at all).

So, the problem is not with PSUs (Corsair RM850x Shift 850W Full Modular 80 Plus Gold PC PSU), which were initially installed in 2 "PCs with problem", but with some other components of 2 "PCs with problem".

2) I have checked 2 GPUs Asus GeForce RTX 4070 12GB GDDR6X ProArt OC Edition Graphics Card and Gigabyte GeForce RTX 4070 12GB GDDR6X Windforce OC with my 3rd PC - they work fine as well. No issues, temperature was 40 - 50 degrees Celsius.

*********
2 "PCs with problem" can't be turned on at all (they are not booting). Any idea what shall I do to eliminate the issues? Where should I start with? How can I check wires, shall I check motherboard and how to do it, etc?