What is Power supply unit?
[[File:PSU-Open1.jpg|thumb|right|upright=1.3|An ATX power supply unit with top cover removed]] A '''power supply unit''' ('''PSU''') is a part of the [[computer]] that converts [[alternating current]] (AC) to [[direct current]] (DC). Other parts of the computer need this DC power so that they can work. The PSU makes sure that the DC output [[voltage]] can be handled by these computer parts.<ref>{{Cite web|title=How to Choose Power Supply for PC: What to Know|url=https://www.intel.com/content/www/us/en/gaming/resources/power-supply.html|access-date=2022-03-13|website=Intel|language=en}}</ref> Modern personal computers always use switched-mode power supplies, which has both efficiency advantages and makes designing for multiple voltage inputs easier. This means that most PSUs can operate in different countries where the power input might change. In the [[UK]], the voltage is 240V 50Hz, whereas in the [[USA]] the voltage is 120V 60Hz, and in [[Australia]] it is 230V 50Hz. Some power supplies have a manual switch for selecting input voltage, while others automatically adapt to the mains voltage. Most modern desktop personal computer power supplies conform to the ATX specification, which includes form factor and voltage tolerances. While an ATX power supply is connected to the mains supply, it always provides a 5-volt standby (5VSB) power so that the standby functions on the computer and certain peripherals are powered. ATX power supplies are turned on and off by a signal from the [[motherboard]].<ref>{{Cite web|date=2022-02-28|title=ATX Motherboard|url=https://elifepc.com/micro-atx-vs-mini-itx-vs-atx/|access-date=2022-03-13|website=Elife PC|language=en-US}}</ref> == References == {{reflist}} [[Category:Computer hardware]] [[Category:Electricity]]