Dualhead not working if is set in Xorg.conf. See log, xorg.conf and video[mp4 format]. With command 'xrandr --output VGA-0 --mode 1152x864 && xrandr --output VGA-0 --right-of DVI-D-0' is everything ok (except plasma, than disable composite, but this is probably related to nouveau_dri.so)
Created attachment 17641 [details] Xorg.conf
Created attachment 17642 [details] Xorg.0.log
http://leteckaposta.cz/306343906 [video with problem MP4 format] I forget: NV4B[7600GS 256MB DDR3]
This is almost certainly not a nouveau bug (since it works with the xrandr tool). I suggest you look at http://wiki.debian.org/XStrikeForce/HowToRandR12 to fix your configuration; for instance you need to use `Identifier "Monitor-VGA-0"' instead of `Identifier "VGA-0"' etc. Also note that DVI-D-0 is probably DVI-I-0 these days.
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