If the above responses to your inquiry find you still wanting, here are my quick notes I used to update and flash my own ROM (I'm hoping all is clear and accurate, but can't be certain):
- Install GPU
- Disable SIP (Command-R, Terminal, csrutil disable)
- Launch DarwinDumper (right-click->Open to circumvent unidentified developer notice); may need to quit and relaunch if stuck “Initialising…”
- Select only BIOS Video
- Click Run (dump will automatically be saved into root folder of DarwinDumper and revealed in Finder)
- Copy ROM file to “bundle” folder and rename as 6798.rom
- Ensure entire path to ROM script contains no spaces; otherwise, this will cause script errors
- Search and replace both 7950mac.efi and efiromheader.rom files “7950” with “7970” (or “HD 7950” with “R9 280X”)
- Launch Terminal and change directory to the script (i.e. cd to “bundle” folder)
- ./makerom.sh --efifile=7950mac.efi --romfile=efiromheader.rom --originalrom=6798.rom --devid=6798
- Ensure there are no errors in output, such as “directory not found”
- The new ROM should be created under 6798.rom.efi.rom
- Copy new ROM to “”atiflash_284” folder on Windows drive
- Boot into Windows
- Launch ATIWinflash.exe
- Select the new ROM to flash with
- Reboot to confirm functionality
- Boot to OS X and re-enable SIP (optional, but gives me peace-of-mind to have it on)
- Connect monitor(s) to each port to confirm functionality.
For steps 1-12, I had placed the "bundle" folder on the desktop to make it easier to perform the Terminal commands.
I've also attached the relevant files used to perform all the necessary procedures, except a hex editor (I used
Hex Fiend). If you get stuck, I'll try to provide additional guidance, depending upon my schedule.
anyway, will do it a little bit later... will post the results.
