editing xorg.conf for AMD W7100?

gongshow

I am trying to set up an AMD W7100 graphics card on a system running RHEL 7.1.



I am unable to make use of the AMD GUI (amdcccle) to setup the monitors. As such I am into the dark art of to editing the xorg.conf



The card has 4X output ports (0-3):



Port 1 to mirror port 0

Port 3 to mirror port 2



The desktop is to be spread out over ports 0 (right monitor) and 2 (left monitor).



My questions:



1. What is the best resource for descriptions on how to effectively edit xorg.conf?

2. Can someone provide an example xorg.conf with a single card 4 port setup?