Many other manufacturers had made power-efficient ARM chips, however, the mainstream computer makers (just a few years ago including Apple) did choose x86 compatibility over power efficiency.
I’m not sure if this is what you were implying, but I don’t know of any x86 processors that can compete with the Arm processors that are in use, on power consumption to performance ratio. Take e.g. Apple’s A12, which compete with their MacBooks in performance, and assuredly draw much less power.
Not too familiar with cpus but if it's known that arm outperforms x86 while also being more power efficient, why aren't everyone using it? Why did it take until now for a major computer manufacturer to switch?
ARM came out the same year as 32 bit x86. Both architectures are very old.
I very much doubt that architecture is all that relevant for their advancements in power usage. Apple's chips contain a significant x86 feature without ruining battery life. Meanwhile, Qualcom is struggling to compete with Apple in both performance and efficiency despite being in the ARM space for much longer.
I'm sure if Apple could've gotten an x64 license ten years ago, they would've made their own x64 chips instead of switching to ARM. When Apple's plans started coming together, there simply were no competing architectures they could base their chips on. MIPS was practically dead already, x64 was extremely closed off, RISC-V wasn't even announced and struggles to keep up today and it wasn't even announced when Apple started selling their own chips.
Maybe they could've licensed POWER6 or an early version of POWER7? The POWER architecture isn't exactly widely used or designed to be power efficient; power management wasn't introduced until 2017 and even then it was optional.
There simply weren't any serious alternatives to licensing ARM and Apple would be stupid to develop an entirely separate CPU architecture for their desktop/laptop/tablet form factors.
This is not entirely true in general sense. Yes, a typical ARM CPU is more energy efficient indeed, but theoretically nothing prevents x86 to be nearly as efficient.
The main reason why Apple silicon is more efficient is that Apple silicon is a mobile chip basically, and competition on mobile is harsh, so all the producers had to optimize their chips a lot for energy efficiency.
On the other hand until apple silicon and recent AMD ascension there was a monopoly of Intel on a laptop market with no incentive to do something. Just look at how fast Intel developed asymmetric Arm-like P/N-core architecture right after Apple Silicon emerged. Let's hope this new competitor will force more energy efficient x86 chips to be produced by intel and amd eventually.
You can get x86 chips designed for laptops in desktop form factors too.
It's not about Arm. All of Apple's M chips so far have been primarily designed for mobile use, and that strongly affects how the power usage scales. It makes a basic comparison of watts not very useful.
I saw an interview with the designers of ARM and they explained how their design was ridiculously more efficient than competitors. Don’t have a link.
Another good source of info is the article over at anandtech. Apple is doing a lot of stuff they Intel can’t because of x86. And also a bunch of stuff that neither Intel nor AMD want to do.
Also don’t forget that Apple is on TSMC 5nm while Intel is for the most part on Intel 14nm which is more or less equivalent to TSMC 10nm.
If we were to go back in time to before apple introduced it’s own SoC and before it had acquired chip design start ups, even before than ARM was on the table as that is what the iPhone ran.
RISC-V wasn’t a thing back then. So the alternatives were MIPS, Power or maybe a home grown instruction set.
So we just have to go with what the reality is now. The apple silicon has been well optimised for performance per watt. And it runs on an ARM instruction set that apple itself helped in the design of.
It's processors. x86 architecture is not as efficient as ARM based, which is why ARM is used in embedded low power devices.
Like the common adoption curve, Intel viewed ARM as a toy, that could never compete with their power capabilities. But ARM got better and better every year, and though x86 got marginally better, they weren't being driven by a market that demanded higher performance. ARM caught up, and due to some exceptionally clever engineering by Apple, has surpassed the capabilities of x86.
We've seen the same story many times before, electric cars will never be competitive, online shopping will never compete with the in store experience, solar/wind/etc will never compete with coal, digital cameras will never compete with film....etc etc
Add your own, there are plenty of examples, but I'm failing to remember others right now.
ARM's only advantage over x86 is power usage and licensing costs. In every other factor, x86 absolutely blows it away. Alot of the newer tech coming from intel is very, very sexy as well.
ARM has its place and is making great strides. But I for one wont be buying a ARM apple anytime soon.
The ARM servers use just as much power as the x86 ones and are typically slower as well. Same for the workstations. Apple makes a great ARM CPU core but nobody else does, and Apple ain't sharing.
Intel tried the low-power x86 with the Atom, didn't really go anywhere. It's true that scaling up an ARM will be equally problematic. But, the point is that they use ARM because they don't want to push the power envelope.
What's there to predict? ARM has always had a stronger low-power presence than x86. Instead of hedging all bets on Atom, they should have kept XScale on hand as a second option. They still have a license to make ARM chips, but the capability that XScale presented never should have been sold.
> Apple has better numbers because it uses the most advanced manufacturing process.
on the contrary, arm is a simpler isa to implement which means radically less circuitry for reading the instruction. modern Intel cpus go so far as having entire systems that translate external x86 instructions to an internal risc based one. That's a huge source of wasted power ie: heat.
<i>ARM has never enjoyed a Op/J advantage over x86.</i>
I'm not sure that exactly accurate, its more accurate to say, that there was a lack of market crossover that allowed similar power or perf envelopes.
That is because ARM did/does make much more efficient CPU's, they just aren't anywhere close to the perf of common x86 cores. AKA a low clocked in order ARM with small caches, etc is more efficient per op but it can't touch even a medium size x86. Intel sort of was in that market for a bit and their cores were efficient too, but the main selling point for an architecture is the software around it, and a 50 mhz in-order x86 can't exactly run modern windows in a reasonable way.
Now that ARM & friends are building higher perf parts, the power efficiency keeps getting worse. When someone makes a 5Ghz ARM core it will likely consume more than a couple mW.
The perf/power ratios have more to do with culture and market than ISA.
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