AO4459 datasheet, a 599 KB PDF from Alpha and Omega Semiconductor for a P-channel MOSFET in an SO-8 package. P-channel parts like this often serve as load switches or input protection on laptop and motherboard power paths. The document shows the pin arrangement, voltage and current ratings and on-resistance, which you need when checking for a short or picking an equivalent. Confirm the marking on the board component, since an N-channel part in the same package will not work in its place.
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 @ic_mosfet_pdf_datasheets. Enginerys does not host this file.
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The standard format for schematics, block diagrams, power-sequence charts and service manuals.