PDF schematic for the NM-D451 laptop mainboard, catalogued under Lenovo, in a 3.13 MB RAR archive. The NM- prefix is the board numbering used by LCFC, the Lenovo-owned design and manufacturing unit. The name does not specify the laptop model, so identify it from the board marking. Schematics like this show power rail generation, EC and charging circuits and signal paths, helping to locate a short or a missing voltage. Confirm that the NM-D451 code and revision on the PCB match before using it.
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 @schematicslaptop. 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.