Quanta KL8 board documentation at revision 1A, provided as an 839 KB RAR archive. The name lists no brand, retail model or full DA board number, so identify the hardware by the KL8 code on the PCB. The archive most likely holds a schematic, used to read power rail names, find regulators and MOSFETs behind a short, follow enable signals and check keyboard, display and USB connector pinouts. Verify that the silkscreened revision agrees with 1A before working from the drawings.
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.