I'm having the same problem on a mac mini G4.
I tried adding Options MacModel mini, and downgradig to xserver-xorg-video-ati_6.6.3-2_powerpc.deb without any luck. (Gutsy had xserver-xorg-video-ati 1:6.7.195-1ubuntu2)
I also tried Option ConnectorTable "4,1,1,1,0,1,2,1"
without any luck.
I'm having the same problem on a mac mini G4.
I tried adding Options MacModel mini, and downgradig to xserver- xorg-video- ati_6.6. 3-2_powerpc. deb xorg-video- ati 1:6.7.195-1ubuntu2)
without any luck. (Gutsy had xserver-
I also tried
Option ConnectorTable "4,1,1,1,0,1,2,1"
without any luck.