MSI Z370-A Pro, works but does not power off or reboot and USB issues

[gretti]

I have a MSI Z370-A Pro. The board does not reboot or shut down from the Windows recovery console. USB communications stop and the status light on USB 1 stays on and does not blink. I have programmed a new BIOS with a CH341A programmer already, swapped RAM, PSU, CPU. The board will power off when the power button is held and resets when the reset switch is pressed, but it will not react to the reset switch if already told by software to shut down or restart. The board will reboot from BIOS after a save and exit command.

The MSI BIOS included the ME firmware for the board. The size of the new BIOS matches the old BIOS. Voltage to the PCH is 1.2V and all voltages around the PCH look normal. Maybe there is a voltage drop when the board changes state from S0.

I installed Windows on an NVMe and stress tested the system with 64GB of RAM. There are no issues in Windows, the board is solid and performs normally. I specifically ran benchmarks that were PCH stressful and there were no failures. The only issue in Windows is that USB sometimes does not work and the system will not power off or reboot. This is the same behavior as from the recovery console tests.

I have not tried an 8th generation CPU on this board.

It is not the ME region. I have corrected and flashed it, no change.

The PCH has been stressed and benchmarked with no apparent issues. I do not think there is a silicon issue.

I tested for a voltage drop in the PCH area. No issues found.

I put a substantial amount of pressure on all four corners of the PCH. No change.

[DynaxSC]

1,2V you mean on pch main core voltage? If so it is too high, should be 1,05V. Other pch voltages are 1,8V, and 3,3V. So 1,2V does not match any of the other voltages too. Check the voltages best on the caps on the pch silicon carrier.

Measure the pch temperature without radiator, it should not exceed 50-55C, if higher it might mean partial pch failure.

[gretti]

one of the caps that sits next to the PCH reads 1,2v I don't have a boardview, but I just checked and the board will power off and reboot from linux, so I'm thinking it's a corrupted ME region or something, I flashed the bios from MSI with the programmer and UEFITool said it had the ME region, but IDK. this board is strange.