I have a laptop with intel 945 card. Xinerama doesnot work there (as I finaly googled after many trials),
but xrandr is fine. Thanks to xrandr - I use 2 monitors with one desktop (seamless) like xinerama. A little problem is that intel 945 accelerates only up to 2048x2048, so I use only 2x 1024x768.
So far so good.
Now I want to connect 3rd monitor that is connected to other PC (slave).
I yumed xorg-....-Xdm and I managed to run it (see elswhere) with the other PC (slave .100.10) and I can have a seamless desktop over 2 computers (laptop control and PC slave)
startx `which icewm` -- /usr/bin/Xdmx :2 -display 192.168.100.2:1 -display 192.168.100.10:0 +xinerama -ignorebadfontpaths
Now the VGA display that is connected to laptop only REPEATS what is on laptops LCD and my xrandr command doesnot work anymore.
RandR extension missing in display 2.0
I want to have 3 monitors ( 2 via xrandr on laptop, the 3rd via Xdmx ) with one desktop....
PS. i tried -xinerama, may be xrandr works only for display :0 ???