Windows 10: PC does not fully shutdown, I suspect WHEA Error

I got the newest Windows 10 1909 (18363.778), and I'm facing this issue for like 2 weeks. Every time i press Shutdown in the Startmenu the pc does not fully shut down. The monitors go black but all the fans keep spinning. After that i just press and hold the power button for 10 seconds until the pc fully shuts down.

Things I have tried:

-Fastboot disable
-BIOS Flash and rollback
-Checked all my Components, with memtest and all the good stuff.
-Removed all other Drives
-Reinstalled Windows a couple of times
-Even tried Windows 1803
-I had some DCOM Errors (RunTimeBroker) which i fixed with some regedit (I saw a post where a guy fixed his shutdown problem with fixing these DCOM Errors)
-Tried without OCing the CPU
-IMEI Driver->PowerManagement-> allow to sleep is unticked

I'm suspecting that this error has to do something with the WHEA-Logger EventID 1 that comes up every time I boot my PC back to normal.

Can anybody help me?

:)

 

WHEA UNCORRECTABLE ERROR

Hi, Andrea.

The reason why your PC shuts down suddenly is because the computer protect itself from data loss. We suggest checking this
link for the troubleshooting steps on how to resolve the error message
WHEA_UNCORRECTABLE_ERROR that you're experiencing on your PC.

Get back to us if you need further assistance.

 

whea warning? cache hierarchy error

I just noticed a whea warning in my event log stating a hardware error was corrected and it was reported by a cpu core. the error type was a cache hierarchy error. i know OCing can cause some of these whea errors, and it seems most people just ignore them, but im just wondering if this one is anything to worry about. my processor is overclocked, but i can pass numerous stress tests and games for hours, without any issues or errors in the even log. i think the pc my have even been idle at the time this was reported , or i was gaming . But again usually there are no errors regardless of what the pc is doing.
anyway, i was just wondering if anyone had some info on this error since googling it comes up with a bunch of different whea errors and no real explanation other than ocing can cause them.

Computer is:
8700K stock, MTE on, 4700mhz auto clock
Asus Z370 Pro Gaming
16GB DDR 3000MHZ ( XMP ON)
Gtx 1080 Ti Aorus
Corsair 750 Rmi
SSD Crucial 525GB
HDD TOSHIBA 500GB
Windows 10 clean install 1709 Creator Fall Update ( 16299.15 build october 2017 ,before meltdown/spectre patch )
All settings in UEFI are stock,defaulted . Only XMP profile is on.

 

Spontaneous PC Shutdowns Following Anniversary Update

Just an update. I still haven't figured out the iSCSI issues -- everything I've read suggest that the 'favorites' tab in the Initiator should list target devices, but mine is empty. The errors in the Event Viewer don't say which device is causing the problem.
I suspect it may be my Drobo unit -- they take several minutes to fully wake up, and yet the error is being logged much earlier than that.

However, the PC shutdowns seemed to have abruptly stopped. I don't believe it's due to anything I have done. The PC has been running for a few days now without it happening.

I'll keep working on this and post anything I learn here.