Circuit schematic for the MSI MS-7313 desktop motherboard, supplied as a 1.08 MB PDF. The trailing 10 in the name most likely marks revision 1.0 of the board, so compare it with the revision silk-screened on the PCB before trusting component values. MS-numbers are MSI's own in-house board codes. Technicians open the diagram in any PDF reader to follow VRM and standby rails, check power-on sequencing, find the parts on a shorted line and confirm the connector pinouts while diagnosing a board that will not start.
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 @pepeelectronica. Enginerys does not host this file.
How to open a .pdf file
The standard format for schematics, block diagrams, power-sequence charts and service manuals.