hello
u have a sandy cpu 2ª generation, the ati dont work, no solution for now, but the intel hd 3000 it works
use smbios macbookpro8,2
and see the kext in s/l/e
AppleIntelHD3000Graphics.kext
AppleIntelSNBGraphicsFB.kext
to see if u dev id is there (0x01168086 example) that is the correct format to insert u dev id
good hack