Connect the power supply to the board, but limit the current. Use the pcbrepairtool to generate a voltage map. Look for the component that is unusually hot.
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The long answer is that the has democratized electronics repair. Ten years ago, only large R&D labs had the ability to find a short circuit on an inner layer of a PCB. Today, a technician with a $300 setup can do the same thing from a kitchen table. Connect the power supply to the board, but limit the current