Arch Linux

Thialfi

Member

Registered: 2016-08-06

Posts: 3

Issues with external Monitors

Hi everyone,

I'm running Arch on a Thinkpad P50 and I'm having weird issues when using external monitors: When the laptop is cold started in the docking station, the monitors are recognised perfectly fine, but when either the screensaver switches on or I try to rearrange the monitors, or when I try to hot plug them, the system becomes unusable due to the external monitors switching off and the laptop screen constantly switching between the desktop and black about once per second. To me it seems like there are some issues with autodetecting monitors, but I know next to nothing about Xorg and google didn't give me any even remotely useful results. Please can someone help/teach me?

Some config details that might be useful:

* Intel graphics deactivated
* Nvidia M1000M with nvidia drivers
* GNOME desktop
* the Xorg log from directly after this situation occured: https://gist.github.com/anonymous/38ebf … a2fe10d8c4
* Monitors are two ASUS PB248Q, both connected via DisplayPort
* see below for loaded nvidia modules

lsmod | grep nv

nvidia_drm             45056  2
nvidia_modeset        757760  8 nvidia_drm
nvidia              11182080  139 nvidia_modeset
drm_kms_helper        118784  1 nvidia_drm
drm                   294912  5 drm_kms_helper,nvidia_drm
[...]

If you need any other information, just ask.  Thanks in Advance.
Thialfi

ewaller

Administrator

From: Pasadena, CA

Registered: 2009-07-13

Posts: 19,784

Re: Issues with external Monitors

Welcome to Arch Linux

Can you get to a stable display by switching consoles (Ctrl-Alt-F2) ?  If not, can you ssh into the box from another computer?
If yes to either of those questions, please post the output of DISPLAY=":0" xrandr when it is not working.  As a reference, you might also post the output of that command when things are working.

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Thialfi

Member

Registered: 2016-08-06

Posts: 3

Re: Issues with external Monitors

Thank you. Things are getting weird. ctrl-alt-F2 did actually resolve the issue right now. The output from  DISPLAY=":0" xrandr is "Invalid MIT-MAGIC-COOKIE-1 keyCan't open display :0", that is with all three screens working right now. I'll keep trying to reproduce just about anything after posting.

Edit: ctrl-alt-F3 gave me a text console, the command gave an error message "No protocol specified. Can't open Display :0"

Last edited by Thialfi (2016-08-18 18:03:53)

Thialfi

Member

Registered: 2016-08-06

Posts: 3

Re: Issues with external Monitors

Okay, still weird. The problem kept occuring after every time I reconnected to the docking station, but with slightly different results every time. Now, I've got the same thing displayed on all screens on ctrl-alt-F1, still with the "Invalid MIT-MAGIC-COOKIE-1 keyCan't open display :0" message

Eventually, though, I got to a black screen. One hard reboot later from within the docking station, things are working fine again. Unless I reconnect, I assume.

Last edited by Thialfi (2016-08-18 18:09:32)