Mini PC power related performance issues

[SKR6588]

I have the weirdest issue with a brand new GMKtec M6 NUC.

 

Upon first boot, things run like absolute garbage. The entire boot process takes easily 10mins.

If it doesn't crash.

If and when I manage to get into windows, the hard disk is at 100%.

A simple reboot is enough to unbrick the system and make everything fast, smooth and trouble free.

From what I have been able to tell, even a shutdown works fine and there are zero issues.

 

The problem comes when I decide to unplug mains power for even a few seconds.

A/m issue reoccurs.

 

The SSD is fine, I've been running it before.

RAM is new and seems to be working given the system runs upon second boot.

BIOS isn't resetting so I rule out the CMOS for now.

I've tried disabling MSI in regedit, disabled fast startup, tried various software fixes I found online.

 

Almost looks like a capacitor issue to me.

 

Any experience with such a fault pattern?