OK, so I decided to buy new hardware since neither the installer, nor apparently something in the boot loader process can even see my SATA hardware on my previous box. (It works wonderfully off a USB drive.) (A whole 'other thread on that, I ended up punting; deciding to buy different hardware.)
I purchased an Intel NUC11TNHi7.
I installed the better of my two SSDs in it. (Made by copying a USB drive install to the SSD.)
The SSD will not boot once you get past the screen that invites you to select a normal boot or whatever the other option is; it locks up and I have to literally pull the plug to get it to work again.
The same is true of my USB install, and it is also true of the installation thumbdrive.
There aren’t a lot of options in the BIOS setup (Nothing whatsoever to do with legacy, for instance), and I’ve seen other threads give a short laundry list of things that should be set; most of which can’t be set in this system.
In other words, it works worse than my old system because even USB boot doesn’t work. I have no idea if QubesOS can see SATA devices because I can’t get it to boot at all.
It goes back to the store in a week if I can’t get it working…at which point I suppose I can get the Librem Mini, but I really don’t want to deal with them given the troubles they have delivering systems.