RAR archive of roughly 2.09 MB linked to an L450 model and the LA-5821 board code, which follows Compal's LA numbering. The brand is not stated, and the contents are not described; such packages usually include a schematic and possibly a boardview. Because Compal produces boards for several laptop makers, match the LA code printed on the mainboard before using the material. Extract it to trace power rails, check signals and locate components, and confirm the board revision agrees with the drawings.
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 @alischematics. Enginerys does not host this file.
How to open a .rar file
Compressed archive — the usual wrapper for a schematic + boardview pair or a BIOS + EC set.