4 ms·
I think he might be correct. Apple A11 has 297 GFlops CPU performance. (1) That “7th gen i5” is apparently i5-7360U. 32 FLOPs/cycle/core (2) * 2 cores * 3.50
by Const-me 8y ago
I think he might be correct.
Apple A11 has 297 GFlops CPU performance. (1)
That “7th gen i5” is apparently i5-7360U. 32 FLOPs/cycle/core (2) * 2 cores * 3.50 GHz (=max turbo) = 224 GFlops.
> the phone CPU is somehow 10 times more efficient per Watt
Not 10 times. The i5’s TDP is just 15W. I don’t know about A11 but high-end Qualcomm chips can be up to 5-6W, just 3 times difference.
> while having the same kind of architecture (general CPU, not GPU/TPU).
That’s a continuum. They both CPUs, they both have SIMD that’s how they achieve that high flop/cycle, but the architecture can be quite different. A11 has 6 cores. Intel spends many transistors, and therefore energy, doing very complicated things: branch prediction, indirect branch prediction, cache synchronization between cores, speculative execution… Apple has full control over OS and software, they can probably get away with not doing some of these. Intel and AMD have to maintain compatibility with all software (including single threaded), built by all compilers and languages, that’s why they have fewer tradeoffs available to them.
(1) https://forum.beyond3d.com/posts/2021926/ https://forum.beyond3d.com/posts/2021926/
(2) https://stackoverflow.com/a/15657772/126995 https://stackoverflow.com/a/15657772/126995