It's all to do with which GPU the port is physically wired to. In most cases it's the Intel chipset wired to USB-C (and the laptop panel), so any monitor connected to that shows up as directly connected to the Intel GPU. In most cases on a dual GPU laptop, the HDMI port is wired to the discrete (Nvidia) GPU.
"In most cases" doesn't mean in all cases. You can get an idea by running: grep . /sys/class/drm/*/status to see which graphics "card" each port is wired to. Also, the frame copy is just a mutter/gnome-shell design limitation. It's possible other desktop environments can composite on each GPU equally without copying, and that's something GNOME aspires to supporting in future. -- You received this bug notification because you are a member of Ubuntu-X, which is subscribed to mesa in Ubuntu. https://bugs.launchpad.net/bugs/2107684 Title: 25.04 boots up to a black screen, both built-in and external monitors To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/mesa/+bug/2107684/+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