An archive of repair files. Shared as “AMD RADEON HD7900 (C381) R1.00A (59YV01P0-VG0A13S).rar” — a .rar file, 110 KB.
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 @bartonarquivos. 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)