X Server will not start. (Driver not found?) Linux Mint 19.1

RaiderZulu · September 25, 2019

So I tried to get my idle Vega VII on Xenoa (my home server) to join in the Folding Fun for https://linustechtips.com/main/topic/1091921-ltt-official-folding-month-2019/

and I broke the install by trying to downgrade the drivers the wrong way (is there a right way?) after trying other things first. I have restored access to TTY1, and after shutting down the firewall, access through ssh, but I still can't get X to start. I have run the uninstall sscript an then the insstall script for a newer version, which got me to that point, but I have hit a wall, even after using dpkg to install the xserver and other obvious components that were not installed by the sscript. I am left with what looks like a driver not found error in the gpu-manager log and something very similar in the Xorg log.

What am I missing? (Do I reaaly need those fallback Vesa drivers?)

Xenoa is built from:

1x Seasonic Prime Titanium 1000

1x Asrock X399 Professional Gaming (*-firmware: American Megatrends Inc. P3.50 12/24/2018)
1x AMD Ryzen Threadripper 2990WX 32-Core Processor (Overclocking locked out by physical switch)
8x 16GiB Corsair Vengeance LPX 3000MHz (description: DIMM DDR4 Synchronous Unbuffered (Unregistered) 2134 MHz (0.5 ns); clock: 2134MHz (0.5ns); box set)

1x AMD Radeon Vega VII (doing next to nothing right now but putting colourful text on the screen.)

3x Crucial P1 NVMe M.2 1000 GB drives
1x NZXT Kraken X62 (If that can wig things out.)
1x Memorex USB DVD-RAM/ROM/R/RW+- drive (Certainly can wig things out if it were left attached and populated.)

Logs attached as a single plaintext file.

xenoaLogs

Oh, and this marks the third time I have had to attempt a rescue of an install from my own stupidity.