Apple logic board firmware for 820-2936 revision B, a dump for the Macronix MX25L6406E flash, which is a 64 Mbit (8 MB) SPI chip, with the Management Engine region cleaned. A clean ME image lets a technician rewrite a corrupted EFI chip without carrying over stale ME data from another machine. Apple prints the 820 number on the board, so verify it before flashing. Serial number and system configuration may need restoring, so read and keep the original chip contents before writing this image.
The button opens the matching file on RM Schematics, or a source page if it is not catalogued there yet. The original attachment is from @biosarchive. Enginerys does not host this file.
How to open a .rar file
Compressed archive — the usual wrapper for a schematic + boardview pair or a BIOS + EC set.
Back up your own chip before writing any dump, and match the full board number and revision. Flashing guide →