MSI MS-7508 motherboard schematic, likely revision 1.0 judging by the trailing 10 in the name. MSI uses MS-xxxx numbers as internal board identifiers, printed on the PCB, which helps match retail model names. The 1.04 MB PDF opens in any reader and is useful for following the CPU VRM and memory supplies, checking standby power and the power-on sequence, and locating components on a shorted line. Check the revision on the board before relying on specific values.
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.