Don't use the AMD's recommendation. They will say more than what you really need. Since you say you're buying new components, including the CPU, you build likely won't need over 450 watts unless you decide to crossfire in the future.
What is your 'budget'? Because 'budget' and RX 580 sort of contradict eachother.
Would you prefer modularity? (I highly recommend it if working with a small case)
Don't use the AMD's recommendation. They will say more than what you really need. Since you say you're buying new components, including the CPU, you build likely won't need over 450 watts unless you decide to crossfire in the future.
What is your 'budget'? Because 'budget' and RX 580 sort of contradict eachother.
Would you prefer modularity? (I highly recommend it if working with a small case)