PDF document for the Dell Inspiron 3158 with board number 14296-1. It is labelled as a boardview but saved in PDF form, which at 209 KB is likely a placement drawing rather than a native boardview file. The 14296-1 number follows Wistron's style, with the suffix giving the board revision. A layout like this helps locate components, connectors and test points on the physical PCB alongside the full schematic. This copy is numbered 2 in its name, so compare it with the other version, which may cover a different side or variant.
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 @hrtechno. 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.