AMD's Raven Ridge Botchy Linux Support Appears Worse With Some Motherboards/BIOS

With my launch testing of the Raven Ridge desktop APUs with the Ryzen 5 2400G and Ryzen 3 2200G there were some stability issues to report and some hangs within games and mode-setting issues. It appears those issues are exacerbated with some motherboards: the past few days with two different AMD B350 motherboards have been a real pain getting the current AMDGPU driver stack working -- and even Linux 4.17 AMDGPU WIP code -- on either of these Raven Ridge APUs...