Arch Linux

Hideaki

Member

From: Seattle, WA

Registered: 2009-01-19

Posts: 37

4K@60Hz, Crazy flickering/no signal

I've ran into a really strange issue. I have a Samsung U28D590D 4K monitor connected to my Chromebook Pixel 2 running Arch. Everything was running fine until I rebooted yesterday. Now I get all sorts of strange behavior on the 4K monitor. On Gnome it will display the login animation then drop to no signal, it will then intermittently flicker on and off between no signal and displaying the desktop. If I maximize a window on the monitor then its a bit more stable, but it will still flicker when I do things like move windows around. Xorg is also using up tons of CPU cycles for apparently no reason. When I'm just idling at GDM the monitor seems to work correctly, it also works correctly in VTs. Openbox will cause the monitor to go crazy moving the entire screen from right to left as if its set on the wrong refresh rate. Setting the monitor down to 1080p fixes all issues on Arch.

I am running xf86-video-intel, but xf86-video-modesetting exhibits the same behavior. The monitor works fine with other computers and ChromeOS does not have any issues and works perfectly. I've tried a different 4K monitor, but running at 30Hz and there are no issues there.

Does anyone have any ideas of why this might be happening or how to solve it?

Note: A workaround I just discovered. Turn the monitor down to 1080p or 1440p then switching it back to 4K appears to fix all issues for that session. Not a great solution but it seems to work for now.

Edit: Here's some xrandr info, nothing seems out of place

[ivan@motoko ~]$ xrandr
Screen 0: minimum 8 x 8, current 6400 x 2160, maximum 32767 x 32767
eDP1 connected 2560x1700+3840+0 (normal left inverted right x axis y axis) 272mm x 181mm
   2560x1700     60.00*+
   2048x1536     60.00  
   1920x1440     60.00  
   1856x1392     60.01  
   1792x1344     60.01  
   1600x1200     60.00  
   1400x1050     59.98  
   1280x1024     60.02  
   1280x960      60.00  
   1024x768      60.00  
   800x600       60.32    56.25  
   640x480       59.94  
DP1 connected primary 3840x2160+0+0 (normal left inverted right x axis y axis) 607mm x 345mm
   3840x2160     60.00*+
   2560x1440     59.95  
   1920x1200     59.88  
   1920x1080     60.00    59.94  
   1680x1050     59.95  
   1600x900      59.98  
   1280x1024     75.02    60.02  
   1440x900      59.89  
   1280x800      59.81  
   1152x864      75.00  
   1280x720      59.97  
   1024x768      75.08    70.07    60.00  
   832x624       74.55  
   800x600       72.19    75.00    60.32    56.25  
   640x480       75.00    72.81    66.67    60.00    59.94  
   720x400       70.08  
DP2 disconnected (normal left inverted right x axis y axis)
HDMI1 disconnected (normal left inverted right x axis y axis)
HDMI2 disconnected (normal left inverted right x axis y axis)
VIRTUAL1 disconnected (normal left inverted right x axis y axis)
[ivan@motoko ~]$ xrandr --listproviders
Providers: number : 1
Provider 0: id: 0x49 cap: 0xb, Source Output, Sink Output, Sink Offload crtcs: 4 outputs: 6 associated providers: 0 name:Intel

Last edited by Hideaki (2015-06-24 18:33:24)