Firmware dump for Apple logic board 820-3330-B, with DV33 and MD103ZPA in the name and an 8MB capacity stated. MD103ZP/A appears to be an Apple part number for the machine configuration, and the 8MB figure points to the size of the SPI flash image. Technicians write such an image to the boot ROM chip with a programmer to recover a board with corrupted firmware. Back up the original chip first, confirm the board number, and check that the image size equals the flash capacity.
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 .zip file
Compressed archive that every operating system opens without extra software.
Back up your own chip before writing any dump, and match the full board number and revision. Flashing guide →