Oh My Gawd!
I think that all that LMDE wanted was a tiny little partition at the beginning of the drive for some UEFI info. IT seems that all that needed to be done was to create a little 200-500 Mb partition. - Something got installed there.
😜 🔫
OK, So this kind of pointed out what rock to start looking under, as it would seem that it wasn't a hardware issue...
https://www.learningpenguin.net/2018/07/13/fix-cannot-boot-after-installing-linux-mint-in-uefi-mode/
But that wasn't the fix, as I didn't have UEFI enabled, and Mint MATE installed just fine. So..
I looked at this...
https://forums.linuxmint.com/viewtopic.php?t=306108
And this...
https://www.learningpenguin.net/2018/07/13/fix-grub-efi-amd64-signed-package-failed-to-install-into-target/
I figured ok, what if I just created an EFI partition 200 - 500 mb in size.
And THAT worked. 🤦♂️
@randynose You might also want to read this overview of how booting actually works on a UEFI motherboard.
https://www.happyassassin.net/2014/01/25/uefi-boot-how-does-that-actually-work-then/
@randynose I didn't think you weren't... but a lot of people (myself included) don't know the details of how UEFI booting works and that post does a great job of covering them.
@ssokolow
I'm aware of the difference. Buf if I've used the same settings countless times, and a particular distro doesn't behave as expected...
It can be a time sink.