My personal experience with the hell that is Error 12.
Yup, disabled - check.
I tried plugging in before selecting, right after selecting, after logon screen, etc
plugging in before selecting mostly results in screen degrading(lines across it and/or flickering)
plugging in after selecting results in black screen
plugging in after login results in error 12
It worked once for five seconds, then windows crashed.
Then it suddenly became unbootable(logo, spin then restart loop)
You’re close. I plug in at the EXACT same time I select windows. Had the same issues as you when timing was different. I’ll be happy to talk y through it on the discord if need be.
You’ve got this champ.
2017 13" MacBook Pro Touch Bar
GTX1060 + AKiTiO Thunder3 + Win10
GTX1070 + Sonnet Breakaway Box + Win10
GTX1070 + Razer Core V1 + Win10
Vega 56 + Razer Core V1 + macOS + Win10
Vega 56 + Mantiz Venus + macOS + W10