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Another way a Two-transistor 5VSB design can kill your board.

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    Another way a Two-transistor 5VSB design can kill your board.

    Received this computer for repair a few months ago, symptom was no-post, one of the two mosfets from RAM VRM had a leg desoldered the other had its pad lifted and both were making bad contact, the reason was a shorted USB port and as the Two-transitor circuit lacks the most basic protections it's output was down to 1.2V, the poor VRM was doing as much as it could to output 1.8V from a 1.2V source and almost goes seppuku, thankfully for customer once the mosfets were soldered and P/S replaced the board worked perfectly, how everything else attached to 5VSB survived and why APW7120 didn't shut down? I don't know, but this board could easily be dead.
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