RAR archive of around 627 KB carrying the name of the ASUS Rampage IV Extreme motherboard, with no indication of its exact contents or revision. Extract it with any standard archiver to see whether it holds boardview, schematic or other service data. Files like these are used to find components and test points, trace CPU and memory power rails and isolate shorts on high-end boards with multi-phase VRMs. Always confirm that the revision inside matches the one silkscreened on the PCB before measuring or replacing parts.
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.