ASUS schematic for the X555LI, provided as a PDF, with RG in the name likely marking a board revision or variant code. Confirm the board revision printed on the PCB matches the document before relying on part references or values. The schematic lets a technician follow power rails from the charger circuit to CPU and graphics supplies, check power sequencing and enable signals, and identify components to measure when diagnosing no power, no display or a short on a supply line.
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 @alischematics. Enginerys does not host this file.
How to open a .pdf file
The standard format for schematics, block diagrams, power-sequence charts and service manuals.