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Troubleshooting Computer Freezing, Locking, and Instant Power Off

Computer Freezing & Locking Up: Bad Capacitors

If your computer randomly shuts off, instantly shuts off, freezes, will not stay on for long, or anything in between like this, there is a good chance that you have a bad capacitor or multiple. In this hub I will be showing you what a capacitor is, and how to find a bad one.

While capacitors can be replaced by a professional or someone with sound knowledge of electronic repair, this will not be covered in this hub.

Capacitor: What Are They?

A capacitor is a battery shaped component in almost every type of electronic computer device in the world. Their main function is to hold a charge steady for a small period of time, and to release it when needed. They help regulate voltage, hence when one is going bad, the voltage will either be high, low, or missing, and then the device fails or malfunctions.

Why Do Capacitors Go Bad?

There are many reasons why they can and do go bad. Some of the common reasons are age, power surges/spikes, brown outs, or systems turning off/on rapidly, and then they are just not built well.

Does Anything Special Happen When They Go Bad?

NOTE: Do not touch the prongs of capacitors without them being discharged first. If one of them discharges into you, it could cause serious injury, and even death.

When capacitors begin to fail or die, a huge handful of problems begin to surface. Below are few examples of what they do when they fail. I do want to note that not all computer problems are the result of a faulty capacitor, however this is one of the easiest places to start looking for signs of trouble.

Motherboard Capacitors:

The most frequent type of capacitor failure are located on the motherboard near the CPU. This is widely due to the fact that a CPU requires a great deal of voltage regulation. If you are getting blue screens, or screen freezes, then this is where you want to look first. The next in line of places to look would be near or on the video card and surrounding slots. Much like the CPU, a video card has heavy voltage requirements as well.

Power Supply Capacitors:

The capacitors inside of a power supply are huge, and are fatal if they discharge into you. Don't disassemble any power supplies without a trained technician. Power supplies fail quit often due to bulging and leaking capacitors. The symptoms of a bad power supply because of capacitors are instant system shut downs (turn offs,) random reboots without error messages or warnings, screen freezes, games may hang or freeze up. Power supplies may act normal, that is until a DVD drive or something like it is requested on. If your system turns off instantly or reboots instantly after accessing a device like a DVD drive, then a power supply test would be a good place to start.

Capacitors That Fail Do One or All of the Following:

1: Bulge

2: Leak

3: Explode (sounds like a .22 cal riffle firing)

Power Supply Bulging and Leaking Capacitor

Bulging Capacitor in a Power Supply

Bulging Capacitor in a Power Supply

Inside of a Bad Power Supply

The images above and below is a shot of some bad capacitors inside of a power supply. This power supply actually appeared to work fine, even passed a power supply general test. That is until there was a demand for more wattage and volts. Then the system turned itself off.

Leaking Power Supply Capacitor Top

Top View Leaking Power Supply Capacitor

Top View Leaking Power Supply Capacitor

CPU Motherboard Capacitor Leak

Leaking CPU Motherboard Capacitors

Leaking CPU Motherboard Capacitors

BAD Processor Capacitors

The pictures above and below are images of bad capacitors that the user was describing as the computer would work for a period of time and then the screen would freeze, with no option other than to shut the system off.

CPU Capacitor Leaks

CPU Capacitor Leaks

CPU Capacitor Leaks

Can Capacitor Failure Be Prevented?

This is a yes and a no answer. Capacitors will eventually fail in time as the chemicals inside them deteriorate. That is not to say, what about premature failure? Here is a list of basic items to help your computer device from prematurely failing due to capacitors.

  1. Keep dust away, blow out the dust from the system periodically as needed per the environment.
  2. Keep room temperatures between manufacturer suggested temperatures. If there is too much heat, electronics will stress, too cold and they don't function correctly.
  3. Moisture is deadly as is completely dry air/static. This is a delicate balance of another environmental control. If the device isn't rated for a high humidity or wet environment, then premature failure is lurking. Static due to dry air can discharge thru the system, if it isn't grounded, may cause stress on the capacitors as well. Operate the computer device per the manufacturers specification.

Bad Caps?

© 2009 Ryan Hutzel

Thanks for Visiting

Ralph Godfrey on December 19, 2011:

thanks for the help i know where to look for help