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A comment on Apple’s M1 Positioning Mocks the Entire x86 Business Model. Parent comment

Re:Apple’s M1 Positioning Mocks the Entire x86 Business Model by userbinator on Friday April 23, 2021 @03:50PM (#26918478)
Leakage is actually a significant part of idle power consumption, especially at smaller process sizes, so much that some CPUs have the ability to turn off parts of caches when idle.

I repeat my stance that x86 instruction decoding is a tiny part of a processor, and things like vector units (which are also often powered down when idle) and reordering logic take far more power.

There's a paper about this that compares the efficiency of different ISAs, and basically concludes that ARM and x86 are no different in that respect. Only MIPS is an awful outlier.

https://www.extremetech.com/extreme/188396-the-final-isa-sho...

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Re:Apple’s M1 Positioning Mocks the Entire x86 Business Model by adwn on Saturday April 24, 2021 @01:25AM (#26922483)
That paper doesn't show what you think it shows. There are too many variables between these CPU implementations to support the conclusion that the ISA doesn't matter for power consumption.
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