I'm slightly worried you might be hitting multiple different bugs there. But instead of worrying, maybe just try the 'modesetting' driver. It might solve even more problems if you get both GPUs using the same driver:
Section "OutputClass" Identifier "Use Modesetting" MatchDriver "radeon|amdgpu" Driver "modesetting" EndSection I'm not sure why those drivers don't yet prefer "modesetting" by default because in Wayland sessions that's exactly what happens anyway. -- You received this bug notification because you are a member of Ubuntu-X, which is subscribed to xorg-server in Ubuntu. https://bugs.launchpad.net/bugs/1923153 Title: [radeon] Display output laggy from iGPU when operating on desktop with attaching AMD R7 430 graphic (dGPU) To manage notifications about this bug go to: https://bugs.launchpad.net/oem-priority/+bug/1923153/+subscriptions _______________________________________________ Mailing list: https://launchpad.net/~ubuntu-x-swat Post to : ubuntu-x-swat@lists.launchpad.net Unsubscribe : https://launchpad.net/~ubuntu-x-swat More help : https://help.launchpad.net/ListHelp