Boardview for the Acer H81-M1 desktop motherboard, revision 1.02A, packed in a RAR archive; the actual layout format inside is not stated. Boardview files show part placement, pin numbers and net names, so a technician can quickly locate VRM parts, test points or a shorted line around the H81 chipset. Open it with OpenBoardView, FlexBV or a similar viewer. Check that the revision on the PCB matches 1.02A before trusting component positions.
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 @zinfo_desktop. 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)