i recently had this problem on my framework laptop.
i connect it to the projector several times per week, and i use arandr to issue proper xrandr commands and configure the second screen.
since one day it started to not work, and i thought, maybe that's because i built 5.17.3 version of linux kernel. then i looked through the kernel configs, built several kernels, even used gentoo's binary gentoo-kernel-bin but nothing helped.
the laptop did detect the external monitor. arandr was seeing it. the screen was "refreshing" when i was connecting or disconnecting the hdmi cable. but the picture was not sent to the external monitor.
eventually i decided to take out the hdmi module from the laptop, and connect it to the other side, moved it from the left side of the laptop to the right side. and that solved the issue!
don't understand why exactly.
i remember when i was younger, so much younger than today, i used to manually assign irqs in bios for different pci devices to get them all work together. i alse remember i was changing pci slots back then. but i was thinking these all were specific to win 9x operating systems, and nt family, and of course linux would handle these all better.
maybe, i don't know, maybe i have some hardware issue, maybe the machine overheated a couple of times and something got damaged. i have no idea what could be the reason.
#gentoo #linux #kernel #hdmi #framework #framework_laptop #laptop #hardware #issue #weird