> As an aside, I'm not convinced by their motivating claim that current processors are power-inefficient. x64 / aarch64 / amdgpu seem to get a lot of maths done

> As an aside, I'm not convinced by their motivating claim that current processors are power-inefficient. x64 / aarch64 / amdgpu seem to get a lot of maths done per watt. Inefficient in the sense that in a general-purpose high-performance CPU the actual work performed by instructions is practically inconsequential compared to the work performed to manage it's execution.