1280x1024 from HDMI port - I know it's possible

[fowie]

I just haven't gotten it to work in OS X. I've got the GMA950 kexts loaded, and I've even patched my DSDT as per Dr. Hurt's instructions. If I try to add "Graphics Mode"="1280x1024x32@60" I get a black screen, and this is the output in the windowserver log:

 

Nov 04 19:30:27 [60] Server is starting up

Nov 04 19:30:30 [60] CGXMappedDisplayStart: Unit 0: no display alias property

Nov 04 19:30:30 [60] CGXPerformInitialDisplayConfiguration

Nov 04 19:30:30 [60] Display 0x5b81c5c0: MappedDisplay Unit 0; Vendor 0x756e6b6e Model 0x717 S/N 0; online enabled (0,0)[1280 x 1024], base addr 0x21c5000

Nov 04 19:30:30 [60] AGCAttach: Couldn't find any matches

 

Help, please?