Did you go back through and be 100% sure that you removed all old Nvidia drivers AND their dependencies? This catches out a lot of folk?
Did you see and follow this? : https://forums.plex.tv/t/pms-version-1-30-1-6562-this-update-stopped-my-transcodes-from-working/826453/97
I’ve not idea why you’d have limited choices for transcoding, that’s a new one on me.
