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KaoruAoiShiho

AMD is not behind at all. Have you seen the latest benchmarks?

https://www.phoronix.com/review/apple-m2-linux/15

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5900HX TDP: 35-80W depending on boost setting. Most gaming laptops set it at 60W+.

M2 TDP: 20W

Power use tends to scale non-linearly past a point - disabling turbo modes would likely significantly reduce the peak power use, and ~18% performance differenceis pretty big buffer to lose.

The 6850u also beats it rather comprehensively according to those same results, and that's only 18-25w.

Really, you'd need everything power normalized, and even the rest of the hardware and software used normalized to compare "just" the CPU, which is pretty much impossible due to Apple and their vertical integration - which is often a strength in tests like this.

The 6850U is comparable in power use and still has a big perf gap against the M2 in mosts tests. Though there are some tests where the M2 leads with a big gap too so maybe it comes down to software in a lot of these. Still it seems to me like Apple is not leading.

It is not, the laptop tested with the 6850U has a 30W PL2 and 50W PL1.

I don't know where you got those numbers. That it can sometimes hit higher peaks is a good thing and shouldn't be counted against it.

https://www.phoronix.com/review/ryzen7-6850u-acpi/6

According to this it should be an average of 19.3 Watts with a peak of 31.85 Watts.

Apple also exceeds the stated tdp during peaks as well but we don't have that information atm. And remember there's a 14% perf gap between the two.

My purpose isn't really to say AMD is definitely better since apple still probably takes the win in overall product, I think the MBA is thinner and that's important to me. But it's to show that x86 isn't behind in performance and that you're not making sacrifices in that department to maintain software compatibility with the x86 ecosystem.

No sacrifices imo, AMD is just fine.

That average is over the entire benchmarking suite, including single thread tests and when tests are loading from disk or otherwise not fully saturating the CPU. Some of those benchmarks in that power consumption number are GPU only!

Take a look at the AOM AV1 power consumption graph (https://openbenchmarking.org/result/2208044-NE-6850U700026&s...), it clearly displays huge drops when the test stops running. The CPU is turboing to 30 watts in 75% of the run.

If you use the 15W hard cap performance numbers (low power mode), performance drops 20-40%.

> Apple also exceeds the stated tdp during peaks as well but we don't have that information atm

We actually do. Notebookcheck recorded 20W usage on a peak MT load (https://www.notebookcheck.net/Apple-MacBook-Air-M2-Entry-Rev...). The MBA is fanless so it's physically impossible for it to substantially exceed that amount without frying your lap.

> And remember there's a 14% perf gap between the two

Like I said, power is not equal at all.

> x86 isn't behind in performance and that you're not making sacrifices in that department to maintain software compatibility with the x86 ecosystem

Comparing the lowest end chip from one vendor to the highest end chip from another is not exactly a great look. Especially when the Arm chip is basically matching the x86 one while having only a few years of software optimization work.

One could argue that the Ryzen's biggest pitfall is that it hasn't adopted a big.LITTLE configuration yet. Alder Lake keeps it's thirsty TDPs while staying relatively respectful of your temps and battery life. It's not quite as granular as Apple's core clusters, but the work with Thread Director is a promising start. Seeing AMD push heterogeneous systems so far down the roadmap virtually guarantees that they won't get Apple-level power efficiency for a while.

On the bright side, AMD has carte-blanche to design whatever they want. Not only can they one-up Intel by implementing core clusters, but they could also one-up Apple by adding power management per-logical-core, or some weird chiplet optimizations. The sky is the limit, really.

Alder lake is much worse temp wise. Look at the new Dell XPS design. They literally had to remove the F keys to make room for additional heatsink to get the newer Alder lake CPUs to work in a reasonable way.

Those Dell XPS are no better than an Intel Macbook, they're designed by people who can't put function before form and consistently screw up their hardware design enough to avoid like the plague. I'm not the least bit surprised they didn't pick the right chip for the job, two years ago it was Dell sending out emails to XPS owners warning them not to leave it asleep in a bag for risk of permanent damage...

I've tried a few Alder Lake laptops now (and daily-drive a 12700k desktop), and I don't really have any complaints about the thermals. Gaming, music production, video editing, none of it can seem to push the CPU past 40c under extended load. It's a solid chip that stands toe-to-toe with it's contemporaries, and I reckon it's going to get scarily good once Intel transitions it from 10nm++ to 5nm.

I agree but that still doesn't invalidate my point. They had to significantly overhaul the thermal system for alder lake. I validating the point that it uses less power then the prior Intel gens.

I do think M2 is more power efficient, but it seems close enough to me. The Thinkpad in real usecase testing has very good battery life, 15 hours etc doing regular work. I just don't have the perspective that the fact it can scale up in power should be held against it. It's pretty typical when you're doing some super computationally expensive processing to be plugged while it's the casual emails etc that has to have great battery life.

> Comparing the lowest end chip from one vendor to the highest end chip from another is not exactly a great look.

Is it anyone else's fault that Apple only has one sku. The M2 is a 20 billion transistor chip while the Rembrandt is a 13 billion transistor chip. I'd argue that the M2 is higher end one. The laptops MBA/Thinkpad compared are the same price.

> Especially when the Arm chip is basically matching the x86 one while having only a few years of software optimization work.

So we agree it matches lol? That's what I was arguing for. Nowhere did I say Apple sucks. I default to using Apple products and have been for almost all my life. I was just trying to make a case that x86 is good enough too hardware wise.

>Unfortunately for testing, as mentioned, right now there is no Linux driver exposing the M2 SoC power consumption under Linux. Hopefully this will be addressed in time but unfortunately meant not being able to deliver any accurate performance-per-Watt / power consumption benchmarks in this article. But when such support does come, it will likely show the M2 indeed delivering much better power efficiency than the Intel and AMD laptops tested. Even under demanding multi-threaded workloads, the M2 MacBook Air was not nearly as warm as the other laptops tested. It's a night and day difference of the M2 MacBook Air still being cool to warm compared to the likes of other notebooks like especially Dell XPS laptops that get outright hot under load. The power consumption metrics should also be more useful/relevant once Linux has working M1/M2 GPU support in place too.

I mean, you shove a fan on the M2 and it beats itself...

It's behind, looks like they are comparing the high end 5900hx with the low end m1 in multi core tests.

Dunno what you're talking about it's definitely the M2 in the test. It's also the same price.

As the other reply mentioned they are testing against the M2, and they are also testing the lower powered AMD part 6850U which does best the M2 in some tests.

Not sure why you came out so strong with such a false statement.

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