Booting into FreeDOS looks promising. Otherwise, I will use the Windows PE trick. Failing that... Win10 maybe? Trying to think of how I could even boot into Windows 10. Install it from USB flash drive to external hard drive, maybe? If I can find an external hard drive laying around somewhere. Or just fill the other empty m.2 slot with a cheap SSD... all for a BIOS update.
(This was a Twitter thread that I reposted here because I figured some folks may have similar experiences and be able to offer tips/tricks?)
"I appreciate SDF but it's a general-purpose server and the name doesn't make it obvious that it's about art." - Eugen Rochko