Reliability of measuring ESR in circuit

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  • cnfcomps
    New Member
    • May 2010
    • 1
    #1

    Reliability of measuring ESR in circuit

    I am trying to repair a socket AM2 ASUS motherboard which will not complete POST (no video, no beeps). I am using the Atlas ESR meter. A row of capacitors near the processor socket all registered high ESR (around 1.84). Now I have de-soldered them, they all register low ESR (around 0.02).

    Is it possible for something else on the board to be causing the high ESR value?

    Would the high ESR value in circuit indicate other problems with the board, or could it be normal?

    Many thanks for any advice anyone can give.

    Matt.
    Tags: None
    • delaware74b
      Badcaps Veteran
      • Apr 2009
      • 628
      • USA
      #2
      Re: Reliability of measuring ESR in circuit

      You were probably reading more than 1 cap while in circuit and thats why it's recommended to test out of the board. This rule holds true for most components, not just caps.
      Stupidity should be a crime, especially for drivers. I have NO patience for them.

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