Schematic PDF titled BM5070, 2.45 MB, with no brand, model or revision in the name. BM5070 appears to be a board or project code, so check that the same marking is printed on the motherboard before relying on the drawing. A schematic like this is used to follow power rails from input to regulators, read signal nets and connector pinouts, and locate the parts involved in a short or a missing voltage. Open it in any PDF reader and use the search function to jump to net names.
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 @cynetitsolution. 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.