Boardview in .bv format for the M57 main logic board, tagged DVT, a design validation test build, and MLB, meaning main logic board. No brand or board number appears in the name, so identify the target from the outline and part labels. As a pre-production layout, some parts may differ from retail boards. The file lets you locate components, follow nets and find test points for measuring rails or isolating shorts. Open it in FlexBV or a similar viewer and compare it with the actual board.
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 @pepeelectronica. Enginerys does not host this file.
How to open a .bv file
Older ATE boardview format, usually found for legacy laptop and desktop boards.