IN FACT we could very well see a bizzare efficiency flip as ARM becomes more power hungry than x86. A lot of anons have pointed out how the ARM macbook pro will consume more than 40 watts of power under load which is around what a modern day x86 high performance laptop uses.

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We've already seen it. The M1 draws nearly 40 watts and loses badly to the 5800u at ~27 watts and that's with a pretty massive node advantage. The M1 is much more efficient at idling/light work due to the small cores, though. big.LITTLE is in alder lake and will likely be in Zen 5.
Then there's the case of graphics. RDNA 2 is easily beating the M1 in perf/watt with RDNA 3 coming with early leaks of 2.5x perf/watt over RDNA 2.
The future for x86 is very bright. Apple will have some massive competition especially since they hit a hard limit for ARM v8 single threaded performance and there isn't enough info about v9 to know of that will still be present in the future.
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