Xrandr dual monitors not displaying correctly.

Question

When I use xrandr to try and run a dual monitor setup instead of having them mirror the screen turns into a mess of pixels. The mouse behaves correctly but I can no longer see windows or anything like that.
I am using the radeon driver and OpenBox. All software is running the most up-to-date versions.
ed ~ $ xrandr -q
Screen 0: minimum 320 x 200, current 1280 x 720, maximum 8192 x 8192
VGA-0 connected 1280x720+0+0 (normal left inverted right x axis y axis) 476mm x 268mm
1920x1080 60.0 +
1280x1024 75.0 60.0
1280x960 60.0
1280x800 59.8
1152x864 75.0
1280x720 60.0*
1024x768 75.1 70.1 60.0
832x624 74.6
800x600 72.2 75.0 60.3 56.2
640x480 72.8 75.0 66.7 60.0
720x400 70.1
LVDS connected 1280x720+0+0 (normal left inverted right x axis y axis) 344mm x 194mm
1366x768 60.0 +
1280x720 59.9*
1152x768 59.8
1024x768 59.9
800x600 59.9
848x480 59.7
720x480 59.7
640x480 59.4
HDMI-0 disconnected (normal left inverted right x axis y axis)
Any attempt to use xrandr (for example to set the correct resolution) results in my entire screen turning into a mess of pixels and I have to restart X to get things back to normal.
I don't have an xorg.conf file at the moment.

Answer 1

I think I have narrowed down the cause to Cairocompmgr, when I turn that off I can switch between my monitors and operate at the correct resolutions.
I don't have any 10-monitor.conf at the moment and even simple xrandr commands like xrandr --output LVDS --auto --VGA-0 --right-of LVDS were making things go crazy. I haven't tried doing dual head yet without cairocompmgr, mind.
Edit: Confirming that with cairocompmgr disabled, everything works as expected.
Last edited by spamuel (2011-12-05 23:38:45)