Archive for an Apple logic board labelled K90I with board number 820-2936-A, revision A, 135 KB in zip format. Apple uses 820-xxxx numbers for its logic boards, and K90I is the internal project code given in the name. The small size suggests a boardview rather than a full schematic, though the contents should be checked. Open boardview files in tools such as OpenBoardView or FlexBV to locate components, follow nets and probe test points, and match the 820 number on the board before relying on it.
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.