A 5.32 MB zip for the ASUS X509FA notebook, EJ056T configuration, which the name links to the X409FB mainboard, revision 2.0. Whether the archive contains a schematic, a boardview or firmware is not stated, so check its contents first. Shared boards across 14-inch and 15-inch ASUS models are common, which is why the board code printed on the PCB matters more than the retail model name. Verify the X409FB marking and revision before tracing circuits or writing any image to the flash chip, and back up the original first.
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 @laptopbios21. Enginerys does not host this file.
How to open a .zip file
Compressed archive that every operating system opens without extra software.