Ubuntu
xserver-xorg-video-ati package

  1. Bug #227520
  2. Comment #5

Comment 5 for bug 227520

Revision history for this message
logari81 (logari81) wrote : Re: External monitor resolution can't be changed on laptop (ati driver)

I definitely found out what is going on here. For me this bug could be considered as closed, as I can define both on the LVDS monitor and the VGA-0 external monitor any of the supported resolutions independently from each other. Not only in Cloned mode but also in Big Desktop mode.

The trick:

After setting the resolutions with xrandr I just have to switch to a VT (e.g Alt+Ctrl+F1) and come back to Xserver (Alt+Ctrl+F7) and then I see the right Resolution.

After that, if I try to play with xrandr again, for example by just starting gnome-display-properties, the resolution of the external monitor switches automatically to the one of the LVDS monitor (and in case this one is not supported from the external monitor I get the sides of the desktop cropped) until I switch to VT and switch back to the Xserver once again.

To me it seems to be a problem of xrandr and not of the driver.

I tried this behavior on both Hardy 8.04.1 and Intrepid Alpha2 and I have observed the same results.