Configure Monitor / Display Resolutions (Ubuntu 10.10)
After installing a KVM switch Ubuntu won't recognize the correct display resolution of the LCD monitor anymore. The following helps to query and set the resolution:
get the correct modeline
cvt h-resolution v-resolution [refresh]
e.g.
cvt 1280 1024 75 # 1280x1024 74.90 Hz (CVT 1.31M4) hsync: 80.30 kHz; pclk: 138.75 MHz Modeline "1280x1024_75.00" 138.75 1280 1368 1504 1728 1024 1027 1034 1072 -hsync +vsync
find out about the current configuration
xrandr Screen 0: minimum 320 x 200, current 1280 x 1024, maximum 8192 x 8192 VGA1 connected 1280x1024+0+0 (normal left inverted right x axis y axis) 0mm x 0mm 1360x768 59.8 1024x768 60.0 800x600 60.3 56.2 848x480 60.0 640x480 59.9 59.9 LVDS1 connected (normal left inverted right x axis y axis) 1280x800 60.0 + 1024x768 60.0 800x600 60.3 56.2 640x480 59.9 DVI1 disconnected (normal left inverted right x axis y axis)
then add a new mode (modeline from cvt) and activate it
sudo xrandr --newmode "1280x1024_75.00" 138.75 1280 1368 1504 1728 1024 1027 1034 1072 -hsync +vsync sudo xrandr --addmode VGA1 1280x1024_75.00 sudo xrandr --output VGA1 --mode 1280x1024_75.00