BYG42 NM-A591 BIOS

BIOS .rar 3.94 MB Shared

BIOS dump for LCFC board NM-A591, the Lenovo Yoga 900S mainboard, labelled with the project code BYG42 and archived at 3.94 MB. The name gives no firmware version or tested status. LCFC, Lenovo's in-house ODM, uses NM-xxxx board numbers. Technicians write such an image to the SPI flash chip with a CH341A or similar programmer to recover a board with damaged firmware. Back up your original chip before erasing, and compare with other NM-A591 images to confirm the size and content suit your 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.

How to open a .rar file

Compressed archive — the usual wrapper for a schematic + boardview pair or a BIOS + EC set.

7-ZipWinRARThe Unarchiver (macOS)

More about .rar files

Back up your own chip before writing any dump, and match the full board number and revision. Flashing guide →

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