Boardview for the Quanta GD3 motherboard, revision C, compressed as a 1.05 MB RAR archive; the exact viewer format is not given in the name. Extract it and open it in a boardview program such as OpenBoardView or FlexBV. Quanta builds GD-series boards for other laptop brands, so confirm the GD3 code and revision C on the PCB first. The layout data lets a technician find components by reference, highlight nets across the board and pick convenient test points for voltage and resistance checks.
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 @alischematics. 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.