Quanta QL2 board package, PCB number DA0QL2MB8F0 at revision 1A, for the LG R490 notebook. Stored as a 1.34 MB RAR archive that is likely to contain the schematic diagram, though its contents are not listed. The DA0 plus project code numbering is Quanta's standard way of identifying a bare mainboard. It is useful for checking against the label on the board itself. Use the file to trace charger and system power rails, find the BIOS flash chip and follow clock and reset lines. Confirm that the revision matches 1A before comparing component values.
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 @IT_SERVICE_WORLD. 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.