After switching over the head node to an X11SDV-4C-TLN2F board (my original X10SDV-4C did not have 10G ports, and I wanted the PCI-E slot for a graphics card), I figured putting together a couple compute nodes using X11SDV-12C-TLN2F models would be a good idea for having a larger number of cores (all of the previous compute nodes have 8) and testing out AVX-512.
The one hitch to using the new X11SDV offerings is the lack of a M.2 slot, and a U.2 port + Oculink in its place. Said U.2 port did not work with M.2 adapters, so I got a couple Intel Optane 905P drives having U.2 connectors. The first board worked flawlessly, and I used it to set up both Optane drives. The second X11SDV would never see the Optane drive no matter what BIOS options I tried (EFI only and dual were both attempted as first measures), though the USB thumb drive with Ubuntu 18.04.2 server worked just fine. Even more maddening was the Ubuntu installer saw the U.2 drive just fine, only the BIOS was myopic when it came to detecting this boot drive.
After much fussing (and swearing), I finally remembered the most recent version of the BIOS was 1.1a, but the second board was only blessed with 1.0b. Why these two boards, from the same vendor and bought at the same, had different BIOS versions is beyond me. Long story short, updating the BIOS on the second board to 1.1a solved the boot issue.
