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It's not the ISA. Modern Macbooks are power-efficient because they have:

- RAM on package

- PMIC power delivery

- Better power management by OS

Geekerwan investigated this a while ago, see:

https://www.youtube.com/watch?v=Z0tNtMwYrGA https://www.youtube.com/watch?v=b3FTtvPcc2s https://www.youtube.com/watch?v=ymoiWv9BF7Q

Intel and AMD have implemented these improvements with Lunar Lake and Strix Halo. You can buy an x86 laptop with Macbook-like efficiency right now if you know which SoCs to pick.

edit: Correction. I looked at the die image of Strix Halo and thought it looked like it had on-package RAM. It does not. It doesn't use PMIC either. Lunar Lake is the only Apple M-series competitor on x86 at the moment.

4 comments

  Intel and AMD have implemented these improvements with Lunar Lake and Strix Halo. You can buy an x86 laptop with Macbook-like efficiency right now if you know which SoCs to pick.

M4 is about 3.6x more efficient than Strix Halo when under load.[0] On a daily basis, this difference can be more because Apple Silicon has true big.Little cores that send low priority tasks to the highly efficient small cores.

For Lunar Lake, base M4 is about 35% faster, 2x more efficient, and actually has a bigger die size than M4.[1] Intel is discontinuing the Lunar Lake line because it isn't profitable for them.

I'm not sure how you can claim "Mac-like efficiency".

[0]https://imgur.com/a/yvpEpKF

[1]https://www.notebookcheck.net/Intel-Lunar-Lake-CPU-analysis-...

Pardon my loose choice of words regarding the Mac-like efficiency. I was referring to the fact that the battery life is comparable to the M3 in day-to-day use, as demonstrated at around the 5:00 mark in the third video I linked.

In the same video, they also measure perf/watt under heavy load, and it's close to the M1, but not the latest gen M4. I think that's pretty good considering it's a first gen product.

Regarding the discontinuation, it's still on shelves right now, but I'm not sure if there will be future generations. It would be awfully silly of them to discontinue it as it's the best non-Apple laptop chip you can buy right now if you care about efficiency.

  In the same video, they also measure perf/watt under heavy load, and it's close to the M1, but not the latest gen M4. I think that's pretty good considering it's a first gen product.

Which video and timestamp? Are you aware that LNL throttles heavily when on battery life?

On battery life, M1 is a whopping 1.5x faster in single thread.[0] That makes M4 2.47x faster when compared to LNL on battery.

So no, LNL is very far behind even M1. That's why there are no fanless LNL laptops.

[0]https://b2c-contenthub.com/wp-content/uploads/2024/09/Intel-...

[0]https://www.pcworld.com/article/2463714/tested-intels-lunar-...

[0]https://browser.geekbench.com/macs/macbook-air-late-2020

I suspect the throttling behavior has to more do with the power settings used during testing or OEM tuning on specific models.

https://www.youtube.com/watch?v=ymoiWv9BF7Q

In this video, they show the perf/watt curves at 8:30. And they show the on-battery vs on-wall performance at 18:35 across a wide variety of benchmarks, not just Geekbench. They used a Lenovo YOGA Air 15 on Window 11's "Balanced" power plan for their tests. The narrator specifically noted the Macbook-like on-battery performance.

Reviewers always use max performance setting for benchmarks and then max battery life for battery tests. That's how people get tricked. When they actually buy the laptop and use it for themselves, they complain that it's slow when on battery life or hot/loud when plugged in.

They're not trying to trick you. In fact when they were measuring perf/watt, the Lunar Lake chip was disadvantaged against the Apple M-series because they had to run the SPEC 2017 tests on Ubuntu for the Lunar Lake chip, which has poorer tuning for it compared to Windows 11. You can see a footnote saying the compilation environment was Ubuntu 24.04 LTS on the bottom left corner of the frame when they show the perf/watt graphs.

They are trying to trick you. All reviewers are told by Intel to run benchmarks in max performance mode and battery either in balanced or max efficiency mode. These modes will throttle. So the performance you're seeing in reviews aren't achievable in battery mode unless you're ok with drastically lower battery life.

Meanwhile, PCWorld is one of the few that actually ran benchmarks while on battery life - which is what people will experience.

Can somebody who knows about this stuff, please elaborate on if it's 'fair' in the first place to compare apple chips with amd/intel chips?

AMD and Intel chips run on loads of different hardware. On the other hand Apple is fully in control of what hardware (and software) their chips are used with. I don't know, but I assume there's a whole lot of tuning and optimizations that you can do when you don't have to support anything besides what you produce yourself.

Let's say it would hypothethically possible to put an M4 in a regular pc. Wouldn't it lose performance just by doing that?

  Let's say it would hypothethically possible to put an M4 in a regular pc. Wouldn't it lose performance just by doing that?

Yes. But an M4 Max running macOS running Parallels running Windows on Arm is still the fastest Windows laptop in the world: https://browser.geekbench.com/v6/cpu/compare/13494385?baseli...

Yeah but an AMD/Intel CPU supports many different types of configurations. Isn't it unfair to compare a chip that only supports one configuration with one that supports many?

It feels to me like we're kind of comparing speeds between a personal automobile and a long haul truck. Yes, one is faster than the other, but that's meaningless, because both have different design considerations. A long haul truck has to be able to carry load, and that makes the design different. Of course they'll still make it as fast as possible, but it's never going to be the same as a car.

Basically what I'm saying is that because it's impossible to strip away all the performance and efficiency improvements that come from apple's total control of the software and hardware stack; is it really possible to conclude that apple sillicon itself is as impressive as they make it out to be?

Yes because it’s still the fastest SoC running Windows. Further more, consumers don’t care if AMD and Intel have to go into more configurations. They care about what they’re buying for the money.

> Further more, consumers don’t care

Well, I'm a consumer, and I certainly care. But I get your point that a lot of people just want a machine that allows them to browse for 10 hours without needing to be charged, and don't really care about anything else.

But do you also get my point? that on some level the chips/hardware are so different that it's like comparing apples to oranges?

That's absolutely wild. I've been loving using the 96GB of (V)RAM in my MacBook + Apple's mlx framework to run quantized AI reasoning models like glm-4.5-air. Running models with hundreds of billions of parameters (at ~14 tok/s) on my damn laptop feels like magic.

  Intel and AMD have implemented these improvements with Lunar Lake and Strix Halo. You can buy an x86 laptop with Macbook-like efficiency right now if you know which SoCs to pick.

This just isn't true. Yes, Lunar Lake has great idle performance. But if you need to actually use the CPU, it's drastically slower than M4 while consuming more power.

Strix Halo battery life and efficiency is not even in the same ball park.

If you look the battery life benchmarks they did at around the 5:00 mark in the third video, you can see that it achieves similar battery life compared to the an M3 Macbook in typical day-to-day use. This reflects the experience most users will have with the device.

It's true that the perf/watt is still a lot worse than the latest gen M4 under heavy load, but it's close enough to the M1 and significantly better than prior laptops chips on x86.

It is a first gen product like the M1. But it does show the ISA is not as big of a limiting factor as popularly believed.

  If you look the battery life benchmarks they did at around the 5:00 mark in the third video, you can see that it achieves similar battery life compared to the an M3 Macbook in typical day-to-day use. This reflects the experience most users will have with the device.

No. The typical day to day use of LNL is significantly slower than even M1. LNL throttles like crazy when on battery in order to achieve similar battery life.

https://b2c-contenthub.com/wp-content/uploads/2024/09/Intel-...

Windows laptops performance while on battery is terrible especially when you put it on power save mode. Macbooks on the other hand doesn't have that problem. It's just like you're using an iPad.

By PMIC, did you mean VRM ?, if not, can you tell me the difference between them ?

I'm not an expert on the topic and don't really know the difference. But in the video they say it can finetune power delivery to individual parts of the SoC and reduce idle power.

Well, Every single CPU need some kind of voltage regulation module to work.

About "fine tune" part, this does not relate to PMIC(or VRM) at all, more like CPU design: How many power domain does this CPU have ?

I don’t know how it is for Apple-M, but for chips I’ve worked on, this can definitely relate to PMIC/VRMs. You can tune the voltage you feed to the various power domains based on the clock speed required for those domains at any given time. We do it with on-chip power regulators, but I suppose for Apple M it would perhaps be off-chip PMICs feeding power into the chip.

it's the other way around. You design PMIC for a given CPU, not designing CPU for a given PMIC(but in Apple case, the engineers can work closely together to come up with something balance).

I always wondered how to gauge how effective Apple's Dialog carveout was, in terms of was it just instant PMIC department or even effective at building a foundation for them? Given their long relationship, I would think it might be pretty seamless.

I assume Apple probably do that more than I know, it is just interesting that their vertical acquisition history feels the most boring and the most interesting.

At least looking from the outside, it feels like relatively small pieces develop into pretty big differentiators, like P.A. Semi, Intrinsity and Passif paving the way to their SoCs.