When using ATI Graphics Card under Ubuntu 11.10, there will be a problem when using dual monitor as follows:
"required virtual size does not fit available size: requested=(2560, 1024), minimum=(320, 200), maximum=(1280, 1280)"
The problem can be solved via this by editing the file "/etc/X11/xorg.conf":
xorg problem--dual-head, Debian vs. Ubuntu:
Now open that file in a text-editor and look for a "Screen" section to which you add a "Display" section, as shown in this example I found on the internet: Section "Screen" Identifier "Default Screen" Device "Intel Corporation Mobile 945GM/GMS, 943/940GML Express Integrated Graphics Controller" Monitor "Generic Monitor" DefaultDepth 24 SubSection "Display" Depth 24 Modes "1600x1200" "1280x1024" "1024x768" "800x600" "640x480" # ADD A VIRTUAL LINE TO PROVIDE FOR THE LARGEST SCREENS YOU WILL HOTPLUG Virtual 2048 2048 EndSubSection EndSection Some more information is available on the man page (man xorg.conf). From the error message you quoted, you may want to choose at least Virtual 2680 1050 in your configuration. Now save the file as /etc/X11/xorg.conf and restart X. Hopefully the error is now gone.
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