Then take away the power allocated to the CPU by default (45-50W?) and double the resulting number.
Question is "why would 2.1GHz core clock not be AMD's original intent for Navi 21"? Or rather, why are we already following the suggestion that AMD had to react by "over"clocking their new graphics cards?
You think the console cpus would really draw 50W? That means 150W x 2 = 300W for the GPU. Add in 40-50W for a PCB and you're now at 350W. If it's a 150W APU, that puts you at 100W x 2 = 200W + 50W for 250W total. Somewhere in the middle is probably a more realistic guess, which is around 300W.