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Apple has been working ruthlessly on battery efficiency for a long time because of the phones and their tendency to minimize battery sizes on Macs for thinness.

The exact design of the cores, how they’re scheduled, the way background stuff is handled on MacOS. All of it. The chips are made on a fantastic process too, but that alone isn’t it. For example they’ve been putting the ability to drop refresh rate really low when nothing changes to more and more of their machines.

It could be that the Intel chip is close, IDK.

But add in other motherboard components, the screen, the OS, the software and system libraries, all are optimized together to hit those numbers. And any of those alone or in combination could be part of the differences.

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> their tendency to minimize battery sizes on Macs for thinness.

Is this actually a thing? Macbook Pro goes up to 100 Wh and almost nobody goes above that because it's the highest capacity battery you don't need special permission to have in a carry on at the airport.

> But add in other motherboard components, the screen, the OS, the software and system libraries, all are optimized together to hit those numbers.

I always find this argument weird because there is so little actual "together" having anything to do with it. Are TSMC's current process nodes efficient? Yes. Can you save power by dropping the refresh rate? Yes. Do the teams doing these things need to coordinate with each other somehow rather than each doing their part independently? Not really.

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I think the Top500 benchmark is biased here. It’s a supercomputing benchmark which means it’s going to heavily weight SIMD and float64 performance, which are things that rarely matter for everyday computing. SIMD has uses in the real world - image or video editing, data crunching, graphics. But consumers basically never use fp64 any more, and so many modern chips have next to zero performance on them. That could easily skew the numbers in intel’s favor.
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I run a number of other benchmarks for a better comparison (linked from my blog post: https://github.com/geerlingguy/sbc-reviews/issues/111).

The Intel chip holds its own for multicore in less bursty workloads, where the fans help.

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An interesting thing there is how much better the Geekbench scores are on Linux than Windows. Makes you think how the Intel/AMD chips would compare to Apple when both running the same OS. Or even just when both not being held back by Windows.
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It's funny, too — in my testing with Asahi Linux, some benchmarks ran better on Linux than macOS on Apple Silicon!
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> consumers basically never use fp64 any more

They do in audio processing. ;)

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I usually use fp32 for the sole reason I can fit twice as many ~24 bit samples per register.
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What? Pretty much every general-purpose calculation on your computer that isn’t an integer is done with FP64. AI may not use it and games may prefer FP32 for many things, but your CPU certainly does a ton of FP64 work.
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Which workloads?
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Literally every workload not named above. It’s the default for a non-integer number.

* Web rendering and almost all web apps (see the JS number type)

* Most things in a game not done on the GPU

* Audio processing

* Most GUI processing/rendering

* Every miscellaneous/scalar calculation these days

Believe it or not, on a CPU this adds up to a lot more than the work you get doing AI processing.

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Yes, it seems to be a new process, 18A. (18 Ångström, allegedly). Manufactured in North America. If the shiny video they did didn't fool me, it's a two sided wafer process, power grid on one side, then the silicon wafer (with through-silicon vias), then transistors, then signal layers.

The processor is this one: Intel Core 5 processor 320 https://www.intel.com/content/www/us/en/products/sku/246018/... in the Wildcat Lake series.

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They have control over the OS and the design of the chip, Intel does not…
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Intel doesn't have control of the design of their chips?

Jokes aside, I don't think the engineering incentive case can be overstated. Apple has been working to squeeze every milliwatt of energy efficiency out of their chips since they started making their own iphone chips in 2010. Their chip is a win if it lets the user have phone battery longer.

Intel and AMD have never been on a power budget. Their chips are a win if they can crank the benchmark performance numbers just a little higher, electricity cost be damned.

This is what you get when you spend 15 years optimizing for energy efficiency per $ instead of raw power per $: a workstation cpu that doesn't even need a fan.

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>It is strange that this chip is so crazy efficient though.

Its only strange if you believe Apples lies.

The truth is, architecture doesn't matter. Single core performance, Apple was always on par with the best chips. Compute is compute, under the hood moving data costs energy, an you can't get away from that.

The reason for "efficiency" of Apple silicon it is because they spent a long time basically optimizing their chips for their specific hardware while running specific programs. Its like building an ASIC to specifically watch youtube vides. When it came to things that are not pipelinable (i.e a lot of branching), the efficieny/battery life statistics flew out the window.

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> And remember the Apple Neo is running an iPhone CPU that is much slower than the M series.

We really need to get over generalization like "phone CPU". Times have changed. Phone or not really isn't the focus.

Per core the A series (cough phone) isn't that much slower than equivalent M series. It's literally the same family just with some extra features, more power, etc.

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I suspect that the comment is more about this not being Apple’s best standard consumer CPU for computers, which would be the M5 (though to your point that’s also in iPads).

It’s good Intel can match anything while staying cool and efficient. That’s a great step. But I’d like to see them match the M5.

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Phone is a sort of short hand for what tradeoffs are likely in the chip. A phone processor is going to prioritize efficiency and thermals over raw performance. Mobile will strike a different balance. While desktop likely prioritizes raw power over performance per watt, thermals be damned!
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Of course, that same "phone" processor gets to operate with battery and thermal headroom of a laptop in the Macbook Neo. The bigger trade-offs are due to the device the chip operates within.
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The biggest tell of the A-series' chip concessions are the ports. A first for Apple, only one USB-C port is Thunderbolt, the other one is USB 2.0 speed. Apple made a computer with a chip made for devices with one port.
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Phones have markedly different thermal limits compared to desktop or even laptops. A laptop CPU can easily suck 30W or more while a phone might not ever reach 10W.
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