Archive of about 1.22 MB for MSI desktop board MS-7345, revision 1.2, in RAR format. No retail model name or content type is given, so extract it to check for a schematic, a boardview or both. MSI marks the MS-number and revision on the PCB, and matching them to this file avoids errors from layout changes between revisions. Technicians use such material to follow the VRM and memory supply rails, check power-on signals and locate components and test points when a board is dead or unstable.
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 @IT_SERVICE_WORLD. 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.