Boardview for the AT6 motherboard in .BRD format, archived as a 440 KB RAR without a stated revision. AT6 is the Quanta project used in HP Pavilion DV6000 notebooks. With the file loaded in a viewer such as OpenBoardView or FlexBV you can click a net to highlight every connected pad, locate parts by reference and find test points for power rails. Because AT6 boards exist in several revisions and variants, check the revision on your PCB and compare component layout before trusting pin 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 @schematicslaptop. 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.