I found that a experienced Server user has a formation of servers with Intel UHD 630 for production on location. Maybe @Jesper could shed some light on this. 
As far as I could see, this might do for a single 1080p channel setup. Now I don’t know much about Ubuntu as my experience is mostly on Windows 10 Pro, and I can’t tell for sure how advanced are developments in Linux version, but I think it’s worth a shot.