Boardview for the ASUS ET2311I all-in-one mainboard, revision 1.3, in BDV format packed as a RAR archive. It maps every component, pin and net, letting a technician locate test points, follow power rails from the adapter input through the regulators and trace shorts to the guilty part. BDV files open in boardview software such as FlexBV or similar viewers. Check the revision printed on the PCB against 1.3 before trusting part locations, because placement can differ between revisions.
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 @pkbiosbdv. 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.