I ran the repair utility of tweaking in order to fix a broken start button issue, and after running it overnight my computer now does not recognize my monitor. It worked fine before, and now I get "Upload VGA driver" in the ASUS PRIME DELUXE message window on the motherboard, along with a "D6" error message. None of this behavior occurred before running Tweak Repair.
Everything lights up fine, including the graphics card-but my monitor does not recognize it and I made no hardware changes to the cabling, etc. between running tweak and my computer not working.
It's now impossible to access BIOS or make adjustments of any kind as the computer seems to "work" with the exception of actually recognizing the monitor. Seems VGA-related. No onboard VGA output on the x299 motherboard complicates this issue...so my computer is pretty much bricked unless I can get the display to start working by fixing this problem sans the display...
ASUS PRIME DELUXE X299
1080 Ti Graphics card
Windows 10 PRO