Firmware image without an extension for the U41SV mainboard, revision 2.0, an ASUS model designation. The 4 MB size matches a 32 Mbit SPI flash chip, so the file is likely a full chip dump ready for a programmer. Confirm the revision silkscreened on the board, read the existing chip contents and keep them as a backup, and check that your flash chip is 4 MB before writing, since an image of a different size will not fit properly.
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 @biosarchive. Enginerys does not host this file.
Back up your own chip before writing any dump, and match the full board number and revision. Flashing guide →