Arch Linux

vermelho

Member

Registered: 2012-05-02

Posts: 8

Dual monitor and hw accel mutually exclusive (using Awesome WM)

Hi I've been using Arch for some months now and I have laptop (Lenovo x220 with integrated intel graphics) with an occasional dual monitor setup. Things were smooth, but I was having issues with video tearing, so I went trough the intel graphics arch wiki page and I was able to turn on hw acceleration and get rid of the video tearing by putting this in my /etc/X11/xorg.conf.d

    # /etc/X11/xorc.conf.d/20-intel.conf
    Section "Device"
       Identifier  "Intel Graphics"
       Driver      "intel"
       Option      "AccelMethod"  "sna"
       Option      "TearFree"     "true"
    EndSection

The problem is that I add that file I no longer have proper dual monitor with extended desktop, the second monitor kind of mirrors the main one.
kind of, because I can move the pointer between the two monitors and is not duplicated, but the desktop (widows and awesome menu) is duplicated on the second monitor, but I can only interact with the windows using the mouse from the main monitor.

I usually do `$ xrandr --mode 1920x1080 --output HDMI1 --right-of LVDS1` to output to the second monitor, and it was working allright.

I've been trough arch and gentoo wiki looking for dual monitor/xorg config stuff to no avail yet.

Last edited by vermelho (2012-08-01 20:18:50)

vermelho

Member

Registered: 2012-05-02

Posts: 8

Re: Dual monitor and hw accel mutually exclusive (using Awesome WM)

Option "TearFree" makes the video playback smother but messes with AwesomeWM windows (duplication), that option is the culprit.

vermelho

Member

Registered: 2012-05-02

Posts: 8

Re: Dual monitor and hw accel mutually exclusive (using Awesome WM)

I found a fix in this thread: http://forums.gentoo.org/viewtopic-p-71 … c9ec76f8b8

Adding `i915.semaphores=1` to my boot params allows me to use the TearFree option in xorg config, without X crashing and with a dual monitor setup.