ZIP archive holding a .cad boardview for the Plano-M motherboard, board number 14230-1. Five digit numbers with a dash suffix are characteristic of Wistron, which uses project code names like Plano for boards it builds for Dell and other brands. The .cad layout opens in boardview software such as OpenBoardView, FlexBV or Boardviewer, revealing part placement, pins and nets. Use it to locate test points and components when diagnosing a short or a dead rail, and confirm the number printed on your PCB matches 14230-1 first.
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 @sboisworld. Enginerys does not host this file.
How to open a .zip file
Compressed archive that every operating system opens without extra software.