ZIP archive of 2.96 MB labelled X750J, a model code in the style of ASUS notebooks, with no brand or board revision in the name. The contents are not described, so check after unpacking whether it holds schematics, a boardview or firmware. Repair documents of this kind are used to trace rails from the DC jack through charger and VRM stages and to locate components. Verify that the PCB revision silkscreen matches, because X750 variants used different boards.
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 @schematiclaptopramkushwaha. Enginerys does not host this file.
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