I am modifying Chameleon-2.0-RC3-r658-src_PCEFIV10.6-src from prasys' blog. It has reboot / shutdown / smbios injecting included and a lot of other nice fixes.
So far I have managed to get DVI output working without the need for a dongle on the vga port or without the need to have two connections to the display at the same time ... thank god for that.
I havent tested the hdmi port yet.
I'll attach the boot file for now.
Do not try this if you do not know how to recover from placing a boot file in the root of your os x partition that does not boot into the GUI, incase something goes wrong you need to know how to fix it.
P.S:Right now this is for dvi on the hd 4670 any other hd 4xxx will feel like they didn't update their boot , tho I would like other hd 4xxx users to post here and give me there dev ids. I will then make a boot for them to test.
Come to #RadeonHD or #MacOSx on irc.osx86.hu for help