sbios settings
given suggestion this may be a BIOS issue, I've posted this issue as a question @,
https://forum.asrock.com/forum_posts.asp?TID=19749&title=x470d4u-p4-20-r...
and pinged ASRockRack tech support via their online tech supp form.
If anyone _here_ knows an appropriate contact @ ASRockRack to link into this discussion, that'd be useful/appreciated!