Firmware dump for Apple logic board 820-00928-A, labelled with the Winbond W25Q64BV flash chip, a 64 Mbit (8 MB) SPI part, packed in a 4.28 MB RAR. Apple prints the 820-xxxxx number with revision letter directly on the logic board. The image is used to rewrite the boot ROM with an external programmer on machines that will not chime or boot. Save the original chip first, since it contains the serial number and other unique data, and confirm the image size fits the chip.
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.
All sources (12)
The same file was posted more than once. If one link is dead, try the next.
| Channel | Posted | |
|---|---|---|
| @biosarchive | 20 Jun 2020 | Open file on RM Schematics |
| @biositechyangiyer | 24 Jun 2020 | Open file on RM Schematics |
| @biositechyangiyer | 28 Jun 2020 | Open file on RM Schematics |
| @laptexlaptopbios | 28 Jun 2020 | Open file on RM Schematics |
| @laptexlaptopbios | 6 Jul 2020 | Open file on RM Schematics |
| @one5technology | 21 Nov 2020 | Open file on RM Schematics |
| @pepeelectronica | 24 Apr 2022 | Open file on RM Schematics |
| @biosdumpcomputer | 26 May 2022 | Open file on RM Schematics |
| @biosdumpcomputer | 26 May 2022 | Open file on RM Schematics |
| @skclappybios | 10 Apr 2024 | Open file on RM Schematics |
| @schematics_bios | 24 Jul 2026 | Open file on RM Schematics |
| @schematics_bios | 1 Aug 2026 | Open file on RM Schematics |
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 →