Just added my experience to bug #58232 at Ubuntu's launchpad.net:
I'm running 2.6.20 32-bit on AMD64 with xinerama and NVidia card - no terminal action here.
Section "Device" Identifier "0 Generic Video Card" Driver "nvidia" BusID "PCI:5:0:0" Screen 0 Option "AddARGBGLXVisuals" "True" Option "DisableGLXRootClipping" "True" Option "XAANoOffscreenPixmaps" "true" EndSection Section "Device" Identifier "1 Generic Video Card" Driver "nvidia" BusID "PCI:5:0:0" Screen 1 Option "AddARGBGLXVisuals" "True" Option "DisableGLXRootClipping" "True" Option "XAANoOffscreenPixmaps" "true" EndSection Section "Screen" Identifier "Main Screen" Device "0 Generic Video Card" Monitor "Main Monitor" DefaultDepth 16 Option "UseFBDev" "true" SubSection "Display" Depth 16 Modes "1680x1050" EndSubSection SubSection "Display" Depth 24 Modes "1680x1050" EndSubSection Option "AddARGBGLXVisuals" "True" Option "DisableGLXRootClipping" "True" EndSection Section "Screen" Identifier "Second Screen" Device "1 Generic Video Card" Monitor "Second Monitor" DefaultDepth 16 Option "UseFBDev" "true" SubSection "Display" Depth 16 Modes "1680x1050" EndSubSection SubSection "Display" Depth 24 Modes "1680x1050" EndSubSection Option "AddARGBGLXVisuals" "True" Option "DisableGLXRootClipping" "True" EndSection
Other than that, both monitors look great, and every other application I've tried works fine.
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