BIOS archive labelled p50NM-A451, which points to a Lenovo-style LCFC board number NM-A451 used in the ThinkPad P50. Apart from that board code, the name gives no revision or version. LCFC uses NM-xxxx numbering for Lenovo mainboards. Such a dump is written to the SPI flash with a programmer to revive a board with damaged firmware. Read the existing chip first and keep a copy, then check that the board marking and the flash capacity match before programming.
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 →