how do.. for work w dual display w matrox g550 cards

view full story

http://askubuntu.com – I installed ubuntu 12.04 on my computer and I have a matrox g550, but I have the problem my dual display is clone. How do I get dual display without being clone? I tried to make one xorg.conf from X -configure and put that file in /usr/share/X11/xorg.conf.d/ and put in this file option xinerama on, but didn't work. Thanks (HowTos)