A schematic diagram for HP hardware (board DAOUW3MB0000). Shared as “HP COMPAQ DAOUW3MB0000_C3A_0902 PDF .rar” — a .rar file, 1.16 MB.
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 @generalbios. 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.
7-ZipWinRARThe Unarchiver (macOS)