Intermitted freeze of 6.7.0U3 ESXI host

Hi,

Having build a new lab server with:

Gigabyte C246M-WU4 Motherboard

128GB Corsair RAM

Intel Xeon E-2176G CPU

Samsung 970 PRO NVMe SSD

Fresh install of ESXI 6.7.0 Update 3 (free version)

I often experience that the host completely freezes with the black/white screen also frozen. No VM's are running, no ping/login to host. Num Lock doesn't work. F2 doesn't work. Everything has freezed.

I know that only the chipset + CPU are on the compatbility list, but I figured that if ESXI could run off an old HP laptop, then why not this machine.

Any suggestions to, how to find the root cause of the freezes? I'd really hate having to change to virtualbox