System stability and PSUs

Collapse
X
Collapse
 
  • Page of 1
  • Time
  • Show
Clear All
new posts
Previous template Next
  • Tom41
    Badcaps Veteran
    • Oct 2005
    • 336
    • England
    #1

    System stability and PSUs

    As I mentioned in a much earlier 'bad caps irony' thread, it's possible to have many capacitors fail and the system still be stable. On the other hand, you can have one tiny little bulge on a single cap, and the system will reboot constantly (both have happened to me).

    What I'm really asking here is that if a PSU cap fails and it starts outputting 'dirty' power, can that be used as a measure of how good the caps on the motherboard are?

    If, for example, you apply dirty power to a board and it remains stable, you have good caps and/or a well designed board. On the other hand, if applying dirty power makes the system unstable, the caps on the board might be bad as well (or the system is under stress).

    I know it's probably not recommended to put dirty power into a motherboard, but can it be used as a test to see if your system is under stress and/or has caps prone to failure? My 2.2GHz machine is packed with genuine Rubycon caps, and yet 'dirty' power caused it to constantly reboot
    You know there's something wrong when you open your PC and it has vented Rubycons...
    Tags: None
    • willawake
      Super Modulator
      • Nov 2003
      • 8457
      • Greece
      #2
      Re: System stability and PSUs

      your problem is still undefined. is it packed with rubycons everywhere? then you probably have some other problem with the board.

      an esr meter would be useful to check the caps in this instance..
      capacitor lab yachtmati techmati

        Comment

        • yanz
          Badcaps Veteran
          • Nov 2004
          • 910
          #3
          Re: System stability and PSUs

          dirty power can kill easily any good caps. that was i always worry of. if i recap the mobo, but left the bad caps on the psu, then.. screw me! recapping the mobo and psu is one packet to do, imho.
          days are so short when you actually do something..

            Comment

            Previous template Next

            Related Topics

            Collapse
            • eryjus
              Heathkit IO-4205 Power Supply Caps
              by eryjus
              Hello,

              First, I am a complete noob with high voltage stuff. I'm learning, but I need help by someone looking over my shoulder.

              I recently came into posession of a Heathkit IO-4205 5MHz Dual Trace Oscilloscope. The documentation is copyright 1978. I'm told it works.

              I opened it up to check the caps before I applied power, and found the following black caps and wanted to know what they were. They are on the power supply board. I was able to read the name and model and came up with, "Nytronics 162J-1, 0.1uF, 20% tolerance, 2000VDC."
              ...
              05-10-2023, 11:21 AM
            • Paxman_Swede
              Identifying caps on an old Zoom 9000
              by Paxman_Swede
              Hello!

              I have two projects on my work bench. One is a friends dead JBL Xtreme speaker with a blown voltage regulator and corresponding bulged and shorted cap. That cap has clear markings so I know what replacement I need for it.

              The other project however is a whole different deal. It's a Zoom 9000 guitar effect from the 90th that has developed a devil hound howl when there is no input from the guitar. I'm guessing caps problem. So, since I don't really use this effect anymore I thought it would be a perfect project to learn on.

              I have studied the board and...
              01-14-2025, 09:51 AM
            • captain150
              Help with switching power supply caps
              by captain150
              I'm trying to repair two old VCRs, they both have bad caps. One has leaky ones, the other would barely run until I subbed in some caps from another power supply I had laying around (though they are the wrong values). This vcr works for an hour or two, but then the power supply starts whining and the picture gets lines in it. I didn't replace all the secondary caps, so another voltage might still be problematic, or the values I used are too far off.
              I've been on mouser and digikey but the options are a bit overwhelming. I just need some new ones that will work. They don't need to be top quality,...
              03-16-2025, 07:34 PM
            • Foetuss
              Gigabyte GA-6OXT :: caps question
              by Foetuss
              Good evening

              I recently aquired a rev 1.1 Gigabyte 60XT, and was suprised of the amount of leaking caps for a motherboard of the P3 era. Especially the way the 330µf caps seems like the housing discolored even.
              Now, there are some 3300µF 6.3V KZG series around the CPU. Would it be OK to replace them with something like EEUFR1A332 ? (Panasonic FR 3300µF 10V). Or was this board designed around very low ESR caps?

              But I was also suprised about the bigger boys, which are 330µF 25V.
              Could it be they used 25V caps because they were cheaper / available at that time?...
              02-11-2025, 12:22 PM
            • momaka
              EVGA e-GeForce 7600 GS AGP 256MD2 [256-A8-N542-T2] with bad caps - fixed
              by momaka
              I did it again – I had to fulfill my inner desire to fix yet another old piece of hardware. This one is actually kind of worthwhile, too – it’s an EVGA e-GeForce 7600 GS AGP video card, model P/N: 256-A8-N542-T2. With the popularity of “retro” PCs from the Win9x to XP era going up, and the diminishing supply of decent AGP cards, it is expected their prices will go up. Or is it? I bought the this video card rather on the cheap side (~$9 USD shipped to my door), because the eBay seller listed it for parts or repair (and correctly noted the bad capacitors.)

              So, here is the...
              06-06-2020, 04:39 PM
            • Loading...
            • No more items.
            Working...