Boardview package for a board identified only as AT6, packed in RAR and marked as containing BDV and BRD files. The brand and full model are not stated, so match the code against the board silkscreen first. BRD and BDV layouts open in boardview software such as OpenBoardView, FlexBV or Boardviewer, showing component placement, pin nets and test points on both sides of the PCB. Pair it with a matching schematic to trace rails, measure to ground at test pads and quickly locate a shorted capacitor.
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.