I’ve been running into an issue with sleep mode and one of my two displays. When the PC wakes, about 10% of the time my main monitor isn’t being detected. Once I log back in to Gnome. I must go to display settings and reenable the monitor. I’m on GNOME 47 using X11running an AMD Radeon RX 7900 XT. Both monitors are using the display port, the one having issues is a 34" LG, my second monitor a 24" Viewsonic doesn’t seem to ever get disconnected.
Hi, @wally501 - welcome to the forum.
I don’t use gnome but I’ve seen similar reports elsewhere [1] and [2].
From those sources I gather it can be related to a new linux kernel and power management not working correctly.
Someone devised a workaround by making a systemd service.
I hope this gives you some pointers. Sorry for not being able to offer a solution.
[1] https://discussion.fedoraproject.org/t/monitors-not-waking-up-after-going-into-sleep-mode/111777/8
[2] a bit older, but arch: https://unix.stackexchange.com/questions/617357/gnome-does-not-wake-up-the-monitor-anymore-on-keypress