External Displays Flickering to Black Under Fedora

I’m having a problem where my external displays are intermittently flicking to black. Except the interesting thing is that it’s completely black except for displaying the mouse cursor and while it’s black I can still move the cursor.

I’m running:
Fedora Silverblue 34 (kernel: 5.14.13-200.fc34.x86_64)
Framework w/i7-1165G7
Caldigit TB3+ Dock
2x 4k 60hz displays via displayport.

It seems to be correlated to the total bandwidth required to drive the displays. When I’m running both displays at 60 Hz I get fairly frequent flickers. When I run either both at 30 Hz or just one at 60 Hz I only get occasional flickers.

I get no flicking on on the internal display.

Anyone have any thoughts?

I’m seeing this behavior also on Arch with GNOME. With one monitor I don’t experience it, but when I added a second that’s when it started. It seems to have something to do with the way windows are being composited, as moving my cursor from one window to another (or across monitors) causes it.

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Good to know I’m not the only one. I also sometimes see the flicker when moving the cursor onto a screen. Also highlighting text

I may have had multiple flicking issues going on.

After rebooting again, I’m seeing both flickers to black with the cursor showing and flickers to black with nothing showing at all.

I set i915.enable_psr=0in my kernel params, as I’ve seen suggested for intel graphics flickering, (and I’ve verified it’s there after the reboot) and it seems to have had no affect from what I can tell.

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I’m not sure if related or the same issue, but I had the same symptoms on Fedora 37 today. (Screen becoming black with pointer still visible and moving. Happens when the pointer moves between the screens.)
In my case I had the internal display set to 60Hz and the external one to 30Hz. When I changed both to be the same (60Hz) the problem disappeared.

11th Gen Framework
GNOME 43.1 (Wayland)
Kernel 6.0.9-300.fc37.x86_64
External USB-C powered 3840x2160 display.

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You’re definitely not alone. There’s some more recent discussion of this issue here: https://www.reddit.com/r/framework/comments/yvkdog/kernel_modeset_warning_with_ubuntu_2210_on_11th/

extradudeguy is trying to reproduce it, I haven’t had a chance to work on recreating it in a 37 live image yet. I’ve had other things taking up my time.

If you’re seeing the same kernel warning and have time you could try to do the same.