Raw 4 MB BIOS binary for a Sony VAIO built on the MBX-223 board, in the M960 sub-variant according to the name. Sony used the MBX designation for its VAIO motherboards, and the extra M-code distinguishes different builds of the same design, so verify it on the PCB. The image is meant to be written straight to the SPI flash with a programmer such as a CH341A or RT809. It must match a 4 MB chip, so confirm the chip capacity and keep a backup of the original contents first.
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 .bin file
A raw, byte-for-byte image of a flash chip: the main BIOS / UEFI, the embedded-controller (EC) firmware, or both.
Back up your own chip before writing any dump, and match the full board number and revision. Flashing guide →