Trying to unlock AI Tweaker on this OEM board/unlock retail options. I have tried few simple things like changing Default to USER in AMI BCP and replacing OEM Setup module with retail one but that doesn't seem to work since BCP crashes after trying to load that rom. Simply crossflashing with a hw flasher didn't work either, the pc didn't boot afterwards

Here is the latest original OEM bios:
Support page: (www) asus.com/us/SupportOnly/CM6870/HelpDesk_BIOS/
Direct dl: dlcdnets.asus.com/pub/ASUS/Desktop/CM6870/P8H77-M-PRO-ASUS-CM6870-0708.zip

And here is the latest retail bios:
Support page: (www) asus.com/supportonly/p8h77m_pro/HelpDesk_BIOS/
Direct dl: dlcdnets.asus.com/pub/ASUS/mb/LGA1155/P8H77-M_PRO/P8H77-M-PRO-ASUS-1505.zip

If you know how to unhide/unlock it, you can upload a rom file without MACs or serials. I can add the info back in and flash with a hardware flasher

@Lost_N_BIOS might have experience with this?

Thank you

Lost as been away since January, the original CM6870 opens and save correctly under AMIBCP 4.55, usually AMIBCP can deal with ur desired option without any problems on this AMI Aptio IV bioses.
Dont see any need of crossflashing. Extract the Intel UEFI image with UEFItool, as rom or bin, then use AMIBCP. Append back the edited image to the CAP again for flashing.

Alternative method, make a spi dump with Intel ME8 FPT tool (always a good method of maintaining an original backup preserving motherboard SN, UUID, Mac), edit and flash again with FPT.

Other option for editing is IFRextract and HEX edit, as alternative to AMIBCP.

Well the thing with AMIBCP is that everything already has "Show: Yes", and setting Access/use to "USER" or "Supervisor" doesn't do anything. I'll have to try to check the setup module. I wasn't able to extract it to text with ifr extractor yet though. Tried PE image as is, whole GUID as is and compressed section as is, but IFR complains about unknown protocol.

And m actually doing all the flashing with a hardware spi flasher because I don't have a hard drive in this machine right now. All the identifying info is backed up

Actually extracting uncompressed with MM Tool worked and IFR extractor recognized it, I think I also found the string for enabling/disabling tabs in hexedit

If AMIBCP has no effect, IFR is the solution, if u cant extract ur doing it wrong.

AMIBCP changes NVRAM + AMITSE/SetupData, not setup module options.
Most BIOS usually go by what's set in NVRAM/stuff changed by AMIBCP
You can edit setup module IFR via hex, or you can make changes live via Grub using setup_var

Bingo! Ai Tweaker is now enabled!

Just in case someone is trying to do the same, I had to do both of these:
Changed all AI Tweaker menu entries in AMIBCP to "Access/use": "USER"
and in addition to that,
Used UEFI Tool (You can use old Alpha 52 to see module names or find the GUID with MM tool then search that in UEFI Tool) to extract Setup>Compressed Section>PE32 Image Section, used hexedit to find 01 00 01 01 01 01 01, and replaced that with 01 01 01 01 01 01 01. Ai Tweaker tab was the zero. Then replaced the original PE image with the modified one.