strange seasonic ss650ht voltage drop

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  • holmes222
    Senior Member
    • Aug 2009
    • 61
    • INA
    #1

    strange seasonic ss650ht voltage drop

    hi all..
    have a problem here with strange abnormally seasonic ss650ht
    type is SS-650HT Active PFC F3
    2 unit psu with same type above, act the same symptom

    the problem :
    - psu work ok with connected to motherboard and one sata hdd
    - connected one ata drive dvd, make sata hdd not detected .. 5v voltage drop to 4,0-4,3v
    - disconnect ata drive dvd, connected another sata hdd .. both sata hdd detected .. 5v voltage between 4,5-4,9v
    - connect another sata hdd .. psu power loop .. 5v voltage drop to 0,5v
    - 3,3v read stable at 3,25-3,35v
    - 12v voltage haven't measured yet ..will do later

    physical check show no burnt,bloated,discoloured component
    what's the problem actually here ??
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