Hi Martin,
same happened for me... Ryzen 7950X3D on X670E, with sporadic reboots. Debugged WHEA to "Bugcheck 9F" with no specific leads/reasons in the dump.
After some research found this thread:
https://www.hwinfo.com/forum/threads/bsod-random-on-laptop-lenovo-legion-5.8297/ and uninstalled HWinfo.
Since then, not a single unexpected reboot or system instability anymore.
I've been using HWinfo for longer than I can recall, and still loving it!
So anything I can do to help debug this to the root cause, I'll be happy to do.
Just let me know what that is.
Cheers
Davy