Archive of 402 KB for a PI945GCM board, apparently a micro ATX desktop motherboard on the Intel 945GC chipset. The name carries no revision number or content description, so open the zip to confirm what it holds. A file this size is consistent with a BIOS image for the small flash chip used on 945 generation boards. When reprogramming, use a programmer that supports the installed chip, save the original firmware beforehand, and check that the model marked on the PCB matches exactly before writing.
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 @laptopchiplevelrepair. Enginerys does not host this file.
How to open a .zip file
Compressed archive that every operating system opens without extra software.