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Ask HN: Why hasn't x86 caught up with Apple M series?

447 points stephenheron | 12 comments | 25 Aug 25 21:50 UTC | HN request time: 1.156s | source | bottom

Hi,

My daily workhorse is a M1 Pro that I purchased on release date, It has been one of the best tech purchases I have made, even now it really deals with anything I throw at it. My daily work load is regularly having a Android emulator, iOS simulator and a number of Dockers containers running simultaneously and I never hear the fans, battery life has taken a bit of a hit but it is still very respectable.

I wanted a new personal laptop, and I was debating between a MacBook Air or going for a Framework 13 with Linux. I wanted to lean into learning something new so went with the Framework and I must admit I am regretting it a bit.

The M1 was released back in 2020 and I bought the Ryzen AI 340 which is one of the newest 2025 chips from AMD, so AMD has 5 years of extra development and I had expected them to get close to the M1 in terms of battery efficiency and thermals.

The Ryzen is using a TSMC N4P process compared to the older N5 process, I managed to find a TSMC press release showing the performance/efficiency gains from the newer process: “When compared to N5, N4P offers users a reported +11% performance boost or a 22% reduction in power consumption. Beyond that, N4P can offer users a 6% increase in transistor density over N5”

I am sorely disappointed, using the Framework feels like using an older Intel based Mac. If I open too many tabs in Chrome I can feel the bottom of the laptop getting hot, open a YouTube video and the fans will often spin up.

Why haven’t AMD/Intel been able to catch up? Is x86 just not able to keep up with the ARM architecture? When can we expect a x86 laptop chip to match the M1 in efficiency/thermals?!

To be fair I haven’t tried Windows on the Framework yet it might be my Linux setup being inefficient.

Cheers, Stephen

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ben-schaaf ◴[26 Aug 25 07:03 UTC] No.45023206[source]▶
Battery efficiency comes from a million little optimizations in the technology stack, most of which comes down to using the CPU as little as possible. As such the instruction set architecture and process node aren't usually that important when it comes to your battery life.

If you fully load the CPU and calculate how much energy a AI340 needs to perform a fixed workload and compare that to a M1 you'll probably find similar results, but that only matters for your battery life if you're doing things like blender renders, big compiles or gaming.

Take for example this battery life gaming benchmark for an M1 Air: https://www.youtube.com/watch?v=jYSMfRKsmOU. 2.5 hours is about what you'd expect from an x86 laptop, possibly even worse than the fw13 you're comparing here. But turn down the settings so that the M1 CPU and GPU are mostly idle, and bam you get 10+ hours.

Another example would be a ~5 year old mobile qualcomm chip. It's a worse process node than an AMD AI340, much much slower and significantly worse performance per watt, and yet it barely gets hot and sips power.

All that to say: M1 is pretty fast, but the reason the battery life is better has to do with everything other than the CPU cores. That's what AMD and Intel are missing.

> If I open too many tabs in Chrome I can feel the bottom of the laptop getting hot, open a YouTube video and the fans will often spin up.

It's a fairly common issue on Linux to be missing hardware acceleration, especially for video decoding. I've had to enable gpu video decoding on my fw16 and haven't noticed the fans on youtube.

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1. lenkite ◴[26 Aug 25 09:55 UTC] No.45024405[source]▶
Hell, Apple CPU's are even optimized for Apple software GC calls like Retain/Release objects. It seems if you want optimal performance and power efficiency, you need to own both hardware and software.

Looks like general purpose CPUs are on the losing train.

Maybe Intel should invent desktop+mobile OS and design bespoke chips for those.

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2. aurareturn ◴[26 Aug 25 10:22 UTC] No.45024590[source]▶

  It seems if you want optimal performance and power efficiency, you need to own both hardware and software.
Does Apple optimize the OS for its chips and vice versa? Yes. However, Apple Silicon hardware is just that good and that far ahead of x86.

Here's an M4 Max running macOS running Parallels running Windows when compared to the fastest AMD laptop chip: https://browser.geekbench.com/v6/cpu/compare/13494385?baseli...

M4 Max is still faster even with 14 out of 16 possible cores being used. You can't chalk that up to optimizations anymore because Windows has no Apple Silicon optimizations.

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3. lenkite ◴[26 Aug 25 14:33 UTC] No.45027111[source]▶
Not really sure whether it makes a difference, but the Parallel VM is running Windows Pro, while the Windows OS on ASUS Gaming Laptop is running Windows Home.
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4. NobodyNada ◴[26 Aug 25 14:35 UTC] No.45027134[source]▶
> Apple CPU's are even optimized for Apple software GC calls like Retain/Release objects.

I assume this is referring to the tweet from the launch of the M1 showing off that retaining and releasing an NSObject is like 3x faster. That's more of a general case of the ARM ISA being a better fit for modern software than x86, not some specific optimization for Apple's software.

x86 was designed long before desktops had multi-core processors and out-of-order execution, so for backwards compatibility reasons the architecture severely restricts how the processor is allowed to reorder memory operations. ARM was designed later, and requires software to explicitly request synchronization of memory operations where it's needed, which is much more performant and a closer match for the expectations of modern software, particularly post-C/C++11 (which have a weak memory model at the language level).

Reference counting operations are simple atomic increments and decrements, and when your software uses these operations heavily (like Apple's does), it can benefit significantly from running on hardware with a weak memory model.

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5. davsti4 ◴[26 Aug 25 14:49 UTC] No.45027339[source]▶
> Maybe Intel should invent desktop+mobile OS and design bespoke chips for those.

Or, contribute efficiency updates to popular open projects like firefox, chromium, etc...

6. lelanthran ◴[26 Aug 25 15:23 UTC] No.45027867[source]▶
> Maybe Intel should invent desktop+mobile OS and design bespoke chips for those.

Wouldn't it be easier for Intel to heavily modify the linus kernel instead of writing their own stack?

They could even go as far as writing the sleep utilities for laptops, or even their own window manager to take advantage of the specific mods in the ISA?

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7. WorldPeas ◴[26 Aug 25 16:48 UTC] No.45029096[source]▶
they /did/ this but notice the "was" at the top of the page: https://www.clearlinux.org/
8. hajile ◴[26 Aug 25 17:06 UTC] No.45029364[source]▶
Intel was working with Nokia to heavily invest into Meego OS until it was killed by Elop+Microsoft.

If it hadn't been killed, it may have become something interesting today.

9. stinkbeetle ◴[26 Aug 25 20:43 UTC] No.45032070[source]▶
> I assume this is referring to the tweet from the launch of the M1 showing off that retaining and releasing an NSObject is like 3x faster. That's more of a general case of the ARM ISA being a better fit for modern software than x86, not some specific optimization for Apple's software.

It's not really even the ISA, mainly the implementation. Atomics on Apple cores are 3x faster than Intel (18 cycles back to back latency vs 6). AMD's atomics have 6 cycle latency.

10. sabdaramadhan ◴[28 Aug 25 05:19 UTC] No.45048663[source]▶
> Maybe Intel should invent desktop+mobile OS and design bespoke chips for those.

Intel is busy fixing up their shit after what happened with their 13 & 14th gen CPU. Making imagine they making OS its called IntelOS and the only thing you can run is only by using Intel CPU

11. sabdaramadhan ◴[28 Aug 25 05:20 UTC] No.45048671{3}[source]▶
Isn't most gaming laptops had Home Singe Language built in? (never had a gaming laptop before)
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12. lenkite ◴[28 Aug 25 07:23 UTC] No.45049419{4}[source]▶
I believe this depends on the OEM.