Arch Linux

jrl

Member

Registered: 2016-02-12

Posts: 20

Xrandr completely disables a monitor

I've connected two monitors to a HP ProBook laptop using a docking station. One of the monitors is connected to the DVI port, another using DisplayPort (DP). The laptop runs on Intel graphics and I've installed xf86-video-intel as well as mesa-libgl packages. I dual boot Arch Linux and Windows 10 (it's a work laptop and I need to use MS software).

On Windows 10 I'm able to use both of the monitors without any issues. When I boot into Arch Linux, the monitors are mirrored. Then I attempt to set the monitors to extend display over both of the monitors using xrandr. And it works well, but only until I pass any command concerning the monitor connected to the DP port (e.g. xrandr --output DP1...). What happens then is that the DP1 monitor flashes a few times and then turns off as if it was not receiving any signal. The other monitor, connected to DVI port, still works but starts showing different glitches and tearing in Firefox. Even when booting into Windows, there is no signal sent to the DP1 monitor and these glitches remain. Only fix I've found is uninstalling Intel drivers on Windows and the reinstalling them. But all this happens every time I attempt to set the monitors right in Arch Linux using xrandr.

Why is this happening and is there a way to fix this so that I could use Arch Linux?

Trilby

Inspector Parrot

Registered: 2011-11-29

Posts: 30,480

Website

Re: Xrandr completely disables a monitor

We couldn't possibly know until you show us the xrandr commands you are using.  I also have no idea what the following could mean, please elaborate:

When I boot into Arch Linux, the monitors are mirrored. Then I attempt to set the monitors to extend display over both of the monitors using xrandr. And it works well, but only until I pass any command concerning the monitor connected to the DP port (e.g. xrandr --output DP1...).

How do you use xrandr to extend the display over both monitors without using a command referring to the second monitor?  And if it works before using the command that references the second monitor, why are you trying to change it?

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"UNIX is simple and coherent" - Dennis Ritchie; "GNU's Not Unix" - Richard Stallman

jrl

Member

Registered: 2016-02-12

Posts: 20

Re: Xrandr completely disables a monitor

Thanks for the reply! Any xrandr command that somehow refers to the DP1 input seems to disable it. Commands that did this for me:

xrandr --output LVDS1 --off && xrandr --output HDMI2 --rotate left --left-of DP1

xrandr --output DP1 --auto

How do you use xrandr to extend the display over both monitors without using a command referring to the second monitor?  And if it works before using the command that references the second monitor, why are you trying to change it?

I was incorrect. I meant to say that xrandr works well controlling other monitors (e.g. xrandr --output HDMI2 --rotate left). It is until I try to somehow adjust the DP1 monitor it disables it. The monitor will occasionally display the output for a few seconds and sometimes give the message that there is no signal, but there is no way to use or control that monitor after refering to it in an xrandr command.