ZIP archive for the Lenovo ThinkPad E480 with motherboard NM-B421, a board number in the NM pattern used by LCFC, Lenovo's own manufacturing arm. At 1.73 MB it likely holds a schematic, a boardview or a small firmware file; the name does not specify which. Use it for tracing rails or locating parts, or for reflashing if it contains a dump. Check that the PCB marking matches NM-B421 and keep a backup of the original chip before writing.
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 @bartonarquivos. Enginerys does not host this file.
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