Overclocking 4890 in OSX

[exabrial]

Using Netkas' Hybrid EFI ROM, I'm able to use a 4890 in Osx

In windows, I can easily clock my card up to 975mhz without stability issues. I'd like to repeat the performance in OSX, because the card runs at a much pokier speed.

Is it possible to hexedit the efi portion to do this? Has this been covered and my searches just unsuccessfully?

 

[MacVidCards]

Just changes speeds in PC portion of ROM. All EFI does is say "Hi, How are ya" and give you a couple boot screens. After that it is running from PC BIOS.

Try using Radeon BIOS Editor. (goes by Rabit, I think)