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AMD's Strix Point: Zen 5 Hits Mobile

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Re: AMD's Strix Point: Zen 5 Hits Mobile

#11

Post by sm_1024 »

wtallis wrote: post #8
sm_1024 wrote: post #2

IMO, the most interesting thing about this line is the battery life---within an hour of MBP3 and within 2 hours of Asus's Qualcomm. Making it comparable to ARM architectures. Which is a little surprising because ARM is commonly believed to be much more power efficient than x86. [1] https://youtu.be/Z8WKR0VHfJw?si=A7zbFY2lsDa8iVQN&t=277

The CPU core's instruction set has no influence on how well the chip as a whole manages power when not executing instructions.

That is fair, I was taught that decoders for x86 are less efficient and more power hungry than RISC ISAs because of their variable length instructions.

I remember being told (and it might be wrong) that ARM can decode multiple instructions in parallel because the CPU knows where the next instruction starts, but for x86, you'd have to decode the instructions in order.

Re: AMD's Strix Point: Zen 5 Hits Mobile

#12

Post by moffkalast »

halJordan wrote: post #6
moffkalast wrote: post #3

[flagged]

[flagged]

Whoever makes something cheap with lots of memory bandwidth and parallel compute gets my vote :)

They somehow managed to put 16GB of HBM2 with a 4096 bit bus on the Radeon VII for $700, it's not like it's impossible. Or at least enough memory channels to rival Apples's M series in some meaningful way.

Besides, what do you expect will the average person be able to run on these Coral tier NPUs? They won't be running Yolov9 all day and all these things can do in practice is accelerate really tiny convnets.

Re: AMD's Strix Point: Zen 5 Hits Mobile

#13

Post by IshKebab »

wtallis wrote: post #8
sm_1024 wrote: post #2

IMO, the most interesting thing about this line is the battery life---within an hour of MBP3 and within 2 hours of Asus's Qualcomm. Making it comparable to ARM architectures. Which is a little surprising because ARM is commonly believed to be much more power efficient than x86. [1] https://youtu.be/Z8WKR0VHfJw?si=A7zbFY2lsDa8iVQN&t=277

The CPU core's instruction set has no influence on how well the chip as a whole manages power when not executing instructions.

Sure, but it's not idle power consumption that's the difference between these.

Re: AMD's Strix Point: Zen 5 Hits Mobile

#15

Post by pohuing »

sm_1024 wrote: post #11
wtallis wrote: post #8

Earlier quoted context omitted.

The CPU core's instruction set has no influence on how well the chip as a whole manages power when not executing instructions.

That is fair, I was taught that decoders for x86 are less efficient and more power hungry than RISC ISAs because of their variable length instructions. I remember being told (and it might be wrong) that ARM can decode multiple instructions in parallel because the CPU knows where the next instruction starts, but for x86, you'd have to decode the instructions in order.

That seems to not matter much nowadays. There's another great(according to my untrained eye) writeup of the lack of importance on chips and cheese.

https://chipsandcheese.com/2021/07/13/arm-or-x86-isa-doesnt-...

Re: AMD's Strix Point: Zen 5 Hits Mobile

#16

Post by wmf »

IshKebab wrote: post #13
wtallis wrote: post #8

Earlier quoted context omitted.

The CPU core's instruction set has no influence on how well the chip as a whole manages power when not executing instructions.

Sure, but it's not idle power consumption that's the difference between these.

When a laptop gets 12 hours or more of battery life that's because it's 90% idle.

Re: AMD's Strix Point: Zen 5 Hits Mobile

#17

Post by carstenhag »

arnaudsm wrote: post #7
sm_1024 wrote: post #2

IMO, the most interesting thing about this line is the battery life---within an hour of MBP3 and within 2 hours of Asus's Qualcomm. Making it comparable to ARM architectures. Which is a little surprising because ARM is commonly believed to be much more power efficient than x86. [1] https://youtu.be/Z8WKR0VHfJw?si=A7zbFY2lsDa8iVQN&t=277

ARM got a lot of hype since the release of the M1, but most users only compared it to the terrible Intel MBPs. Ryzen mobile has been consistently close to Apple silicon perf/watt for 5 years. But got little press coverage. Hype can be really decorrelated from real world performance.

But how is this the case? I never saw a single article mentioning that a non-Mac laptop was better.

(Random article saying M3 pro is better than a Dell laptop https://www.tomsguide.com/news/macbook-pro-m3-and-m3-max-bat... )

Re: AMD's Strix Point: Zen 5 Hits Mobile

#18

Post by Filligree »

arnaudsm wrote: post #7
sm_1024 wrote: post #2

IMO, the most interesting thing about this line is the battery life---within an hour of MBP3 and within 2 hours of Asus's Qualcomm. Making it comparable to ARM architectures. Which is a little surprising because ARM is commonly believed to be much more power efficient than x86. [1] https://youtu.be/Z8WKR0VHfJw?si=A7zbFY2lsDa8iVQN&t=277

ARM got a lot of hype since the release of the M1, but most users only compared it to the terrible Intel MBPs. Ryzen mobile has been consistently close to Apple silicon perf/watt for 5 years. But got little press coverage. Hype can be really decorrelated from real world performance.

Ryzen mobile is consistently close, yeah. But with the sole exception of the Steam deck, I've yet to see a Ryzen mobile-bearing laptop, Windows included, which is close to the overall performance of the Macbook.

Re: AMD's Strix Point: Zen 5 Hits Mobile

#19

Post by dzaima »

pohuing wrote: post #15
sm_1024 wrote: post #11

Earlier quoted context omitted.

That is fair, I was taught that decoders for x86 are less efficient and more power hungry than RISC ISAs because of their variable length instructions. I remember being told (and it might be wrong) that ARM can decode multiple instructions in parallel because the CPU knows where the next instruction starts, but for x86, you'd have to decode the instructions in order.

That seems to not matter much nowadays. There's another great(according to my untrained eye) writeup of the lack of importance on chips and cheese. https://chipsandcheese.com/2021/07/13/arm-or-x86-isa-doesnt-...

The various mentioned power consumption amounts are 4-10% per-core, or 0.5-6% of package (with the caveat of running with micro-op cache off) for Zen 2, and 3-10% for Haswell. That's not massive, but is still far from what I'd consider insignificant; it could give leeway for an extra core or some improved ALUs; or, even, depending on the benchmark, is the difference between Zen 4 and Zen 5 (making the false assumption of a linear relation between power and performance, at least), which'd essentially be a "free" generational improvement. Of course the reality is gonna be more modest than that, but it's not nothing.

Re: AMD's Strix Point: Zen 5 Hits Mobile

#20

Post by jeffbee »

wmf wrote: post #16
IshKebab wrote: post #13

Earlier quoted context omitted.

Sure, but it's not idle power consumption that's the difference between these.

When a laptop gets 12 hours or more of battery life that's because it's 90% idle.

And while it's important to design a chip that can enter a deep idle state, the thing that differentiates one Windows laptop from the next is how many mistakes the BIOS writers made and whether the platform drivers work correctly. This is also why you cannot really judge the expected battery life under Linux by reading reviews of laptops running Windows.
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