The primary function of a Desktop Power Supply or Dell Power Supply or generally computer power supplies is to convert AC electricity to DC electricity because it is the AC electricity that comes from the socket or walls but the computers need DC electricity to function.

Computer power supplies generally come in 2 main flavors: switched mode and linear mode. Let us discus each of them briefly so that you can have a better understanding of them.

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Linear power suppliers

A linear computer power supply requires very few and simple steps to convert the EC electricity into the DC electricity at a safe level for a computer. They constantly expend energy and usually dump the extra energy as heat. Typically, these power supplies normally require larger components basically for delivery of high power. This is something that limits these power supplies to just smaller power applications in most cases.

The main advantage of linear power supplies is that their output often has little noise. This makes them ideal for all places and environments including laboratories and hospitals.

Switched mode power supplies

Switched mode computer power supplies are equipped with internal switches which control the general flow of electricity that is going into all other parts of the power supply. Even though this is something that adds complexity, it still has some benefits. First, the switched mode power supply uses far less amount of electricity as compared to linear power supply. Secondly, the switching action of the switched mode power supply generates very high-frequency AC electricity. Due to the high-frequency AC electricity, there are some components like transformers and inductors that this type of power supply allows to be smaller.

The main disadvantage of switched mode power supplies is that the switching usually creates a lot of noise which must always be shielded in order to prevent leakage. This is done by filtering the noise in the output.

Laptop power supplies

A Desktop Power Supply is somehow different from a laptop power supply. For instance, a Lenovo Power Supply converts the power from the socket into electricity that can be used by the laptop. The electricity is usually divided between the internal power supply and the external adapter supply. The adapter then converts the electricity from the socket to something that the internal power supply can be able to use. This is typically a higher DC voltage as compared to what a Desktop Power Supply usually furnishes.