My microwave uses 1200 or 1500 watts and does not need a dedicated circuit. Sure, I don’t run it continuously for an hour, but that has nothing to do with whether or not it needs a dedicated circuit.
A 16A circuit allows for 3.8kW or something like that @ 240v.
With these ludicrous power requirements, you may in fact need to rethink how you use your power. E.g. if on same as a non-heat pump drier, you'd have to make a choice between gaming and drying clothes.
Having said that I saw a reference to a 4090 offering 95% of the perf at 60% of the power usage if undervolted, so that becomes an attractive option now.
I absolutely love my 5800X3D's insanely low power usage (insane = performance per watt for gaming in simulator titles where it runs circles around Intel).
