SX280s show no physical sign of bad caps

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  • robotman2009
    New Member
    • Aug 2010
    • 4

    #1

    SX280s show no physical sign of bad caps

    Dear badcaps.net,

    Sometimes, I get some SX280s free from my wife's work when they get rid of them...I actually fixed a bad monitor given to me from my wife's work by replacing some bad caps. But anyway I have 2 Dell sx280s USFF that are showing no physical signs of badcaps. But they have the symptoms of badcaps....shutting off suddenly etc.

    From what I've been able to glean from the forums, and since I don't have anymore cash to buy some nice diagnosing equipment, it seems I am going to have to desolder the caps and test each one with my voltmeter. I have a pretty nice voltmeter that measures capacitance. So I was going to give this the old college try and see what happens. My only concern is that I read that sometimes a voltmeter can show that a capacitor is good when it actually is starting to fail...or actually may be ok when computer is off but when things heat up inside case, capacitor loses its ability to do its job.

    I am a 3rd grade teacher and want to get them running for my classroom. But there is no major rush. Any advice on progressing would be welcome.
  • Topcat
    The Boss Stooge
    • Oct 2003
    • 16956
    • United States

    #2
    Re: SX280s show no physical sign of bad caps

    Recap it anyway, especially the 2200uF and the 3x 820uF by the SB and NB chips. That will usually cure that problem, I've had a few do that.
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    • robotman2009
      New Member
      • Aug 2010
      • 4

      #3
      Re: SX280s show no physical sign of bad caps

      So replace every capacitor?...but especially the ones you mentioned?

      Comment

      • Topcat
        The Boss Stooge
        • Oct 2003
        • 16956
        • United States

        #4
        Re: SX280s show no physical sign of bad caps

        Everything 820uF and up. Also, there's a 22uF 25v next to the CMOS battery that likes to fail.
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        • stj
          Great Sage 齊天大聖
          • Dec 2009
          • 31036
          • Albion

          #5
          Re: SX280s show no physical sign of bad caps

          that 22uf will make the system slowdown & freeze - it's a real bitch!

          Comment

          • robotman2009
            New Member
            • Aug 2010
            • 4

            #6
            Re: SX280s show no physical sign of bad caps

            Thanks guys

            Comment

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