Nvidia 555 drivers causing no display on secondary monitor
Currently, if I upgrade to 555 drivers, my second monitor will not show a display despite it being detected by Plasma and xrandr. Additionally, if I do get past the log screen on wayland, my framerate/refresh rate is abysmal but not reported by xrandr. Unplugging the second monitor fixes the issue.
Sometimes, before login, I simply get a black screen/no signal which I've seen other post about but have not seen anything about second display not displaying.
Initially happened on EOS but swapped over to Bazzite and same issue. Reverting to the last 550 drivers and both monitors work fine.
I've tried setting nvidia kernel parameters for wayland and disabiling GSP firmware with no luck. Both monitors connected to the GPU. Issue on both x11 and wayland. Any input would be great.
UPDATE: Connecting the second display with DisplayPort instead of HDMI resolved the issue and I can log into wayland no problem with both functioning displays
Ryzen 5600x
3070ti
Primary Monitor is connect via DisplayPort
Secondary Monitor is connected via HDMI
Is one of your monitors HDR? I've been getting similar issues (EndevourOS) ever since upgrading to 555, where both of my monitors are black/no signal when logging into Wayland. Unplugging my primary monitor fixes the secondary monitor, and it seems like HDR is the problem in my case - https://bugs.kde.org/show_bug.cgi?id=488941
After deleting ~/.config/kwinoutputconfig.json, I could login. I did some tests and the issue happens when HDR is enabled. In the config file that put "highDynamicRange" and "wideColorGamut" to "true". Just changing "highDynamicRange" to "false" doesn't work, but if I put both to "false", I can login again.
Simply deleting kwinoutputconfig didn't fix the problem for me but I haven't tried setting it as read-only yet (Probably a good idea to back it up first). My X11 is working normally so I'll stick with that until this bug is resolved.