Schematic in PDF form for the Dell Vostro 3450 laptop, an 805 KB document. The name gives no board number or revision, so compare the ODM number silkscreened on the motherboard with the title block inside before trusting it. Technicians use such diagrams to follow power rails from the charger input through to the CPU and memory regulators, identify the EC and BIOS chip, and locate fuses or MOSFETs when hunting a short. Any PDF reader opens it, and the text search helps find net names quickly.
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.