Tracking down +5v Standby problem on MB

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  • b_s_d
    New Member
    • Nov 2007
    • 3
    #1

    Tracking down +5v Standby problem on MB

    I have an Intel D865GBC MB that does not power-up because something is holding "PSU On" marginally high. The power supply itself and switch have been ruled out, so the problem is definitely on the MB. There are no signs of damaged caps, hot spots on any chips, or physical damage to traces. The only other symptom is that the LM1117 regulator on the +5V Standby circuit gets very hot - no real surprise as it looks like there is a short somewhere downstream. I replaced the LM1117 on the off chance it was the problem, but still no joy.

    Could a defective cap be causing this? Does anyone know of any tricks for tracking down this sort of problem?

    I'm about convinced the board is DOA, but thought I'd check here before recycling it.

    Thanks and regards, Bob
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