Identifying Bad Capacitors

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Electrolytic capacitors are one of the few components used in game consoles & home computers that slowly change over time. This is considered normal, and depending on usage, quality of original parts, etc., replacement will probably be necessary at some point.

Certain hardware is prone to having outright defective capacitors. Defective capacitors tend to go out of tolerance quickly, leak, or sometimes explode. These systems should have their capacitors preemptively replaced to prevent damage to surrounding components and traces.

See the Bad Capacitors category for systems with known issues

Bad Capacitors, Non-Electrolytic

Polystyrene and tantalum caps seem to be the other two types that can have problems in older gaming/computer hardware, although not with the frequency of electrolytic.

If you need to kill some time, read the Wikipedia "Types of Capacitors" article. That article can give you a good idea of what a suitable replacement or upgrade may be for a defective cap.

Identifying Bad Capacitors

Sometimes, bad caps can be identified by certain physical characteristics, including:

  • Bulged appearance
  • Domed tops
  • Asymmetrical or stretched plastic jacket
  • Fluid leaking
  • Split vents

Symptoms of defective capacitors may include:

  • Excessive noise in audio or video, including 60hz audio hum or rolling bars in video
  • Scratchy, distorted, or missing audio
  • Low contrast, blurry, or distorted LCD displays
  • Intermittent or outright failure

Bad surface mount capacitors are not always easy to identify. Besides being smaller, they are constructed in a slightly different manner than leaded capacitors and typically mounted flush to the PCB. They tend to leak downward, and due to their flush mounting, the fluid will not be visible until a significant quantity has leaked out.

Read the guide on converting surface mounts caps to traditional leaded caps

Gallery of Bad Caps