RAR archive of 2.77 MB labelled only for the Dell Vostro 2420, with no board number, revision or content description in the name. It may hold a schematic, boardview or BIOS dump, so unpack it and identify the files before relying on them. Read the board code printed on the Vostro 2420 motherboard and compare it with whatever the documents show, since Dell models often came on more than one ODM board. If a firmware image is inside, back up the original SPI chip with a programmer before writing anything.
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 @SCHEMATICWORLD. 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.