easy xinerama setup for matrox g450 - working but with minor flaw
 

I have tried out a lot of xorg.conf configurations to get my matrox g45mdvp32db vidiocard to work in xinerama, on a dell powerdge 750 server, installed with ubuntuStudio 12.4. Every one crashes trying to use xinerama. But one works - with a minor flaw! the setup I have found is on this site: http://www.r3uk.com/index.php/tech-t...in-ubuntu-edgy
The flaw is that the left screen will not start on boot. My way of dealing with this is to use a different xorg.conf file when fireing up the computer and then through sudo gedit overwritting the xorg.conf with the right one. this is a very annoing process. Is there anybody out there who knows how to alter the xorg.conf file to switch on the left screen on boot? The xinerama-working xorg.conf looks like this:

Section "Device"
Identifier "Matrox Graphics, Inc. MGA G400 AGP 1"
Driver "mga"
BusID "PCI:3:0:0"
Option "OldDmaInit" "True"
Screen 0
EndSection

Section "Device"
Identifier "Matrox Graphics, Inc. MGA G400 AGP 2"
Driver "mga"
BUSID "PCI:3:0:0"
Option "OldDmaInit" "True"
Screen 1
EndSection

Section "Monitor"
Identifier "1"
Option "DPMS"
EndSection

Section "Monitor"
Identifier "2"
Option "DPMS"
EndSection

Section "Screen"
Identifier "Default Screen 1"
Device "Matrox Graphics, Inc. MGA G400 AGP 1"
Monitor "1"
DefaultDepth 24
EndSection

Section "Screen"
Identifier "Default Screen 2"
Device "Matrox Graphics, Inc. MGA G400 AGP 2"
Monitor "2"
DefaultDepth 24
EndSection

Section "ServerLayout"
Identifier "Default Layout"
Screen "Default Screen 1"
Screen "Default Screen 2" RightOf "Default Screen 1"
EndSection

Section "ServerFlags"
Option "Xinerama"
EndSection

I am using the xserver-xorg-video-mga driver providded by ubuntu

many houres later trying to edit the xorg conf to get around the flaw, leaves me with this observation: if the second Section "Device" and Section "screen" is configured with a "1" in the end - not "2", the left monitor will appear on boot - but in clone mode - then you can edit back to "2" and the xinerama is on. the conclusion must be that it is the command "Matrox Graphics, Inc. MGA G400 AGP 2" that does not turn on the monitor. is it possible to trigger xserver to use the "1" command to start the monitor and then use "2" to xinerama?