Capacitor rating and substitution rules in motherboards and Graphics cards

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  • Koda
    Badcaps Veteran
    • Aug 2011
    • 317
    • Macedonia

    #1

    Capacitor rating and substitution rules in motherboards and Graphics cards

    I'm asking this because I read another topic https://www.badcaps.net/forum/showthread.php?t=20791
    and I see that capacitors of higher capacitance can adversely affect other components such as diodes in bridge rectifiers and similar components.

    I work mostly on motherboards and video cards and that's why I'm asking specifically for those components. Now I'm not an electronics expert by a long shot but had great success with recapping. Sometimes what I do when I'm out of caps of certain uf value I substitute them with caps of higher value but never higher then 50% plus of the original and never had any problems doing so. For an example I just recapped an old 7300 GT with sacons and was completely out of caps so I salvaged some mobo caps with good ESR (measured). Original sacons were 5x1500uf 16v, 2x1000uf 6.3v and a single 470uf 6.3v. The replacements I used were 3x2200uf 16v Rubies ZL and 2x1800uf 16v Rubies MBZ for the 1500uf sacons, 2x1000uf Panasonics FM for the 1000uf and a 470uf 25v Pana FM. The card Runs extremely well, passed 25hrs of furmark without a hitch but can higher UF ratings give me problems in the future?
    Guns don't solve problems. I'll take 12
  • Rulycat
    Badcaps Veteran
    • Apr 2010
    • 724
    • United Kingdom

    #2
    Re: Capacitor rating and substitution rules in motherboards and Graphics cards

    Often boards using crappy caps are designed to take a wider range of uf and so on... because then the unpredictable caps won't make the board unstable.

    Also bear in mind that caps can have a -+20% tolerance so a capacitor with 1000uf on it may well be up to 1200uf.

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