Firmware dump for the Acer Extensa 4420 built on the BIWA motherboard, Wistron board number 06237-3M. Packed as a 601 KB RAR, it is intended for recovering a laptop whose BIOS chip is corrupted, typically by reprogramming the SPI flash off-board or with a clip and an external programmer. Wistron designs and manufactures many Acer notebooks, which is why the board carries this five-digit code. Read and keep the original contents before writing, and confirm the dump size equals the chip 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 .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 →