I have plugged in a PNY XLR8 500GB M.2 NvMe drive in a Delock PCIe card and stuck it in Riser 3 on my Poweredge r630 - Although the drive doesn't show up anywhere in BIOS, I could boot the Ubuntu installer from a USB thumb drive and the installation saw the drive just fine. It installed successfully and after a reboot I get a new option in my UEFI boot menu "ubuntu" - but it is greyed out!
If I go to system settings -> Boot settings I can see the system recongizes the drive/os but it is listed as "Unavailable: ubuntu"
If I try to tell the system to boot from this drive regardless, it will say something like "Booting from ubuntu - boot failed"
How come UEFI can see the installed OS / drive just fine (it seems) but fails to boot from it? Is there something I can toggle somewhere to make this work?
I found a post on Reddit where a user had the same problem but he offered no solution except some vague suggestion that one could try to boot from a USB stick first and then hand over boot to the NvMe drive - but how that would work exactly I am not sure.
Any suggestions are most welcome!