Lenovo service archive for the DL470 design, board number NM-B021 revision 1.0, packed as a 9.83 MB ZIP. The NM- prefix is the LCFC numbering pattern used on Lenovo laptop motherboards, with DL470 being the project code. A package this size probably holds a schematic and may include boardview data for locating parts and test points. Before relying on rail names or component values, confirm that NM-B021 and revision 1.0 are printed on the board being repaired.
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 @ITHINKHS. Enginerys does not host this file.
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