RAR archive of 4.20 MB named Q77M D2H, which corresponds to a Gigabyte desktop motherboard built on the Intel Q77 chipset. The name does not reveal whether it holds a BIOS dump, schematic or other files. Gigabyte boards often use dual BIOS chips, so if firmware is inside, check which chip it belongs to, back up both originals with a programmer, and verify the image size against the flash capacity before writing anything.
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.
7-ZipWinRARThe Unarchiver (macOS)