Schematic for an IBM-branded X201i, judging by the file name, supplied as a 1.62 MB PDF with no board number or revision given. The i suffix normally marks a lower-spec variant, so parts may differ from the standard model. The document helps a technician follow power rails, check enable and power-good signals, locate test points and identify components when diagnosing a no-power or short fault. Compare markings on the motherboard with the title block before trusting 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 @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.