RAR archive of 244 KB for the M5A97, with the name pointing to board revisions 1.02 and 1.02X. No brand or file type is given, so inspect the contents to see whether it holds firmware, a schematic or boardview data. Revision matters here, so read the version printed on the PCB before relying on it. For a BIOS image, back up the existing chip first. For board data, use it to follow power rails and find components.
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.
7-ZipWinRARThe Unarchiver (macOS)