Archive of about 3 MB labelled PA_HM65 with version V5.21, pointing to a board based on the Intel HM65 chipset, though no maker or board number is given. The size fits a BIOS image for the typical small SPI flash on such boards, but confirm the contents after extraction. HM65 is a mobile chipset, so this is likely for a laptop or compact system. Match the board marking and version with the file, read the original chip with a programmer, and keep that backup before flashing.
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 @biositechyangiyer. 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.