Archive named GC6C, 87.5 KB in ZIP format, with no brand, model or board number in its title. GC6C seems to be a variant code related to sibling files GC6 and GC6A, possibly a project or board revision code, though the name alone cannot confirm it. The small size points to a boardview or firmware image rather than a full schematic. Open the archive to identify its contents and verify against the markings on the motherboard before relying on it for diagnostics or flashing.
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 @ITHINKHS. Enginerys does not host this file.
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Compressed archive that every operating system opens without extra software.
Built-in OS tools7-Zip