ASUS K54LY motherboard package, revision 2.1, packed as a ZIP of about 2.01 MB. The contents are not listed, but a file of this size typically holds a schematic PDF, possibly with a boardview. Schematics show the power sequence, voltage regulators and signal connections, so you can trace a missing rail or an absent enable signal. A boardview helps place parts physically on the PCB. Check that the silkscreen on your board reads revision 2.1, because component placement and values may differ between revisions.
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 @ITHINKHS. Enginerys does not host this file.
How to open a .zip file
Compressed archive that every operating system opens without extra software.