Zalman ZM300A-APF repair, bad 5V Standby

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  • Chungalin
    Badcaps Veteran
    • Jul 2014
    • 422
    • Spain

    #1

    Zalman ZM300A-APF repair, bad 5V Standby

    This Zalman ATX PSU was bought back in 2003 by a friend and I got it in 2008. I've been using it on a daily basis since then. I always disconnect it from power at night.

    Since past week I noticed that it didn't want to start from cold state. After a while it eventualy started normally, but this "while" was growing everyday.

    This PSU has been never serviced. Not bad considering it has quite a few TEAPO's:

    https://www.badcaps.net/forum/showpo...3&postcount=70

    Nothing bloated. I check ESR and I find abnormal reading (>2Ω) in a TEAPO 1000uF/10V, from 5V standby rail. Replaced both TEAPO from that rail and working.

    A rather sentimental repair.
  • cpt.charlie
    Badcaps Veteran
    • Sep 2013
    • 270
    • Spain

    #2
    Re: Zalman ZM300A-APF repair, bad 5V Standby

    Check a small cap at the primary side on the 5VSB power supply, these tend to lose it's value and cause these kind of problems (i think it's a 50v maybe 22uF)

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