What is the typical function of the power supply unit (PSU)?

The typical function of the power supply unit (PSU) is to distribute power to internal components. The PSU is a critical piece of hardware within a computer system that converts the alternating current (AC) from an electrical outlet into the direct current (DC) that the computer's components require to operate. It provides the necessary voltage and current to the motherboard, CPU, hard drives, graphics cards, and other peripherals, ensuring that all components receive stable and reliable power for proper functioning.

This function is crucial as without adequate power distribution, the system may fail to boot up, risk damaging components, or experience instability during operation. The PSU typically has various connectors to accommodate different components and may also include features like voltage regulation, which helps maintain consistent power levels.

In contrast, upgrading storage capacities refers to increasing data storage space, which is not the role of a PSU. Providing cooling to the system is typically the responsibility of fans or cooling systems rather than the PSU. Lastly, although the PSU does play a part during startup when it provides power, initializing software is the role of the motherboard and the BIOS/UEFI, which handles the execution of the necessary startup instructions once power is supplied.