Laptop schematic named X51RL, supplied as a 2.57 MB PDF. No brand, board number or revision is stated in the name, so confirm these on the drawing itself. The diagram is useful for following power rails from input to the CPU and memory regulators, tracing signals, finding test points and identifying components near a shorted line. Any PDF viewer can open it. Because related X51 variants exist, make sure the board marking matches this drawing before relying on it.
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 @schematicslaptop. 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.