The power supply unit (PSU) you need for an AMD 7600 should ideally have a power rating that can comfortably handle the total power draw of your system, with some headroom for potential upgrades or overclocking. A good starting point would be a PSU rated around 500W to 600W with at least an 80 PLUS Bronze certification for efficiency. Some highly recommended options include the Corsair CV550, Gigabyte P650B, or the Cooler Master MWE 650 Gold V2.