RAR archive of 340 KB for a P7Q57-M DO motherboard; the name does not reveal whether it holds a boardview, schematic or firmware. The naming matches ASUS desktop boards, and DO usually designates the variant with business features, but confirm the contents after extraction. A file this small typically holds a boardview or a compact service document. Compare the model and revision silkscreened on the board with what is inside before using it for tracing power rails, locating parts or checking signals.
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 @boardview. 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.