hi mate

try extracting your dsdt and try using some mods in this dsdt and recompile to dsdt.aml in root / or /extra

http://osx86.co/f84/dsdt-for-a8n-sli...working-t6299/

you can pull your dsdt using dsdte (best) or from a bios file using dsdt patcher for windows if you need to mess around with it pre boot.

to find graphics card location, install dsdte and open registry (ioregistryexplorer) the gfx0 section needs ot be placed underneath the current graphics card location in your dsdt

remove the nvcap if it doesn't match yours and clear package value at top of gfx section to leave empty brackets () before compiling value will be generated on compile to .aml

use graphicsenabler still to calculate the correct nvcap and you can insert it into dsdt afterwards

if you need hdmi, you can try the mac 8800 rom with bootflags VBIOS=Yes UseNvidiaROM=Yes 10de_04xx.rom in /Extra xx = your nv pid

let us know how you get on. your bios settings are also important. try to disable all that you dont need