What is the primary function of a power supply in a computer?

The primary function of a power supply in a computer is to convert AC power from the wall outlet into low voltage DC power. This is essential because computer components, such as the motherboard, CPU, and other peripherals, operate on low voltage DC electricity. The power supply takes the higher voltage AC current—typically provided by the electrical outlet—and transforms it into the various low voltage DC outputs required by the internal components, usually 3.3V, 5V, and 12V.

By performing this conversion, the power supply ensures that all parts of the computer receive the appropriate voltage to operate effectively and safely. This role is crucial, as supplying the wrong type or voltage of power can damage the components or lead to improper functioning.