Help! Can't get AMD Firepro V5900 graphics card working with Mountain Lion #GPU

Hello all,



I just got mountain lion up and running on my system and booting fine with the chameleon bootloader. It's installed on the following hardware:



Motherboard: ASUS Sabertooth X79

CPU: Intel Core i7 3930k

SSD: OCZ Vertex 4

RAM: 32GB



Nevertheless, I can't get it to work with my graphics card. I can only achieve a resolution of 1024 x 768. I would really appreciate it if anyone could provide with some guidance as to how to get it working. Not very many people have built systems with this line of gpus, so there isn't much documentation on fixes. So far, I've tried two different things:



1. This procedure listed on MacOSx86.net: http://www.osx86.net/view/1998-hd575...on_10.7.2.html

2. The procedure listed by Úll Mac in this tonymac forum: tonymacx86 Forum ? Information



Neither of them worked for me.



Thanks and please let me know if you need anymore information.





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