RAR package of 2.08 MB carrying board code 3CESL with suffix RH-13, which reads as a revision designation. The file name says nothing about the document type, so extraction with 7-Zip or WinRAR is needed to see whether it holds a schematic, layout or dump. Revisions RH-12 and RH-14 of the same code sit alongside it and may differ in part placement. Match the marking printed on the motherboard exactly before using it to trace rails or locate faulty components.
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 @cyberlanelectonik. 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.
7-ZipWinRARThe Unarchiver (macOS)