An ATX Power Supply is a crucial component in desktop computers, providing the necessary electrical power to the system. It converts the alternating current (AC) from a wall outlet into direct current (DC) that the computer's components, such as the motherboard, CPU, and graphics card, require to function properly. Typically housed in a metal case, an ATX power supply includes various connectors to supply power to different parts of the computer. It comes in different wattage ratings, allowing users to choose one that meets their system's power needs, ensuring stable and reliable operation.