Rar archive for the P8H61-M LX PLUS desktop board, part of the H61-chipset micro-ATX family, without any revision or file type stated in its name. Unpack it to see whether it contains a BIOS dump, a schematic or boardview data. For firmware, compare the board revision on the PCB and use a programmer to back up the original flash before writing; for diagrams, rely on them to check standby rails, VRM circuits and component locations when hunting a short or no-power fault.
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.