Ubuntu
xserver-xorg-video-ati package

  1. Bug #227520
  2. Comment #20

Comment 20 for bug 227520

Revision history for this message
Richard Hansen (rhansen) wrote : Re: External monitor resolution can't be changed on laptop (ati driver)

I too am experiencing this bug, and I too am using the open source radeon driver (xserver-xorg-video-radeon-1:6.9.0+git20081003.f9826a56-0ubuntu2 from Intrepid, although it was also broken in Hardy). Sometimes the second monitor is at the proper resolution (1680x1050) and position (to the right of my laptop screen and shifted up a bit). Other times it's stuck at 1280x1024, mirroring the laptop display (1400x1050) no matter what I do with xrandr or gnome-display-properties. Even when the second monitor is not displaying what it should, 'xrandr -q' says that the desired resolutions and positions have been applied.

Usually a reboot will fix it. Killing X (Ctrl-Alt-Backspace) never fixes it. Trying to switch to another VT always fixes it. (Oddly, when it's not working, Ctrl-Alt-F1 doesn't switch to VT #1 -- it just corrects itself and stays at VT #7. If I try to switch to VT #1 when the displays are at their correct resolutions and positions, it switches -- and switches back -- properly.)