Boardview package for the N73SV mainboard, revision 2.0, supplied as a 215 KB RAR archive. BDV in the name marks it as boardview data, which shows component placement, part designators and net connections on both sides of the PCB. Technicians use it to find where a capacitor or MOSFET sits, locate test points and follow a shorted net across the board. Typical tools such as OpenBoardView, FlexBV or Boardviewer open these formats. Verify the board actually reads rev 2.0 before trusting component locations.
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 @cyberlanelectonik. 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.