The problem is the modeline from your monitor for the 1920x1080 mode is greater than 165 Mhz which is the current cut off for single link mode in the driver: (II) RADEON(0): Modeline "1920x1080"x60.0 172.78 1920 2040 2248 2576 1080 1081 1084 1118 -hsync +vsync (67.1 kHz)
It should work if you specify a modeline with a lower clock E.g., Modeline "1920x1080R" 138.50 1920 1968 2000 2080 1080 1083 1088 1111 +hsync -vsync -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/915408 Title: Garbled display on external screen when using 1920x1080 instead of 1920x1200 To manage notifications about this bug go to: https://bugs.launchpad.net/xserver-xorg-driver-ati/+bug/915408/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
