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Picking The Right Power Supply: What You Should Know

Don't Get Burned: Safety Before Stinginess

Chinese Firecrackers

While this description may sound a little whimsical, there’s a serious implication to consider. Often, what seems like a bargain can turn out to be a potentially flammable component capable of taking out your whole system when it makes its grand exit.

The Most Important Protective Circuits In Modern PSUs

Knowing is half the battle, so says the G.I. Joe PSA, and that’s why we want to present this info. Below you’ll find a table with the most important abbreviations for protective mechanisms found in modern power supplies. If you make sure these features are included with your PSU of choice, you can prevent your hardware from falling prey to an unnecessary failure.

AbbreviationProtection 
OVP Over-Voltage Protection (primary and secondary)
UVP Under-Voltage Protection (primary and secondary)
NLO No-Load Operation
SCPShort-Circuit Protection
OCP Over-Current Protection
OPPOver-Power Protection
OTPOver-Temperature Protection
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A decent PSU should contain a supervisor (protections) IC. Sadly, there are still some companies that sell super-cheap models with a conventional fuse and MOV (Metal Oxide Varistor) as “equipped with short-circuit and surge protection.” While this may be true technically, a combination like that is a recipe for disaster.

When Buying Cheap Can Be Really Expensive

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Here we have two examples of what can happen when a company cuts corners; things can get really hot. We think these pictures speak for themselves. Do yourself a favor and get a decent power supply.

And with these educational images, we’ve come to the end of our primer on switching power supplies. Now that we’ve gone over the theory, it’s time to apply what we learned to the real world. To that end, let’s look at some of the components in a computer and how much power they consume.

Aris Mpitziopoulos
Aris Mpitziopoulos is a Contributing Editor at Tom's Hardware US, covering PSUs.