Having just found this topic, I figure I would throw in my frustrations as well.
I got the Asus Prime B350M-A two weeks ago, and ever since setting it up, it would continually lock up hard, requiring a hard reset every 16-24 hours. I tested the ram, and it went 48 hours without issue. I tried copying all my data off, and doing a clean unraid setup, and it still locked up. I went so far as to swap out the motherboard with the ASRock Fatal1ty AB350 Gaming K4, and it is still locking up. I never setup any VM's. I did install windows on an SSD in the system, just to see if Windows would crash, and it was fine. This is really starting to get irritating, going on almost 3 weeks of issues.