Small ZIP for MSI board MS-15821 revision 2.1, with GN20-P0-A1 in the name indicating an NVIDIA GPU variant. At 401 KB it most likely contains a boardview or small firmware file rather than a full schematic set. MSI prints the MS-number and revision on the PCB, so check both before relying on it. Boardview files open in tools like OpenBoardView or FlexBV for finding components, nets and test points; firmware should only be flashed after backing up the original chip.
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 @boardsscanrepo. Enginerys does not host this file.
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