PDF schematic of 3.91 MB for a mainboard labelled NB3029, apparently the WSCH MB variant at version V4 A, as the name states. No brand is provided, so confirm the board marking against the PCB. A full circuit diagram like this lets a technician follow the power-up sequence, identify what feeds each rail, read component values and check which signals go to the EC. Any standard PDF reader opens it; use search for net names to jump between pages 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 @ShareMan_Electronic_Files. 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.