381–390 of 446 posts
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Not arguing, but I would think there is (and always has been) very wide demand for fastest single core perf. From all the usual suspects? Thank you.
Only Intel and AMD actually attempt to deliver fastest single-thread performance. Apple has made the decision that almost-but-not-quite-the-fastest is good enough for them. And that has made all the difference.
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It's not, because Apple purposefully lied on their marketing material. Letting a 3090 go on full blast brings it pretty much in line in perf/watt. Your 3090 will not massively thermal throttle after 30 minutes either, but the M1 Ultra will. So, yes, if you want to look good on pointless benchmarks, a M1 ultra ran for 1 minute is more efficient than a downclocked 3090.
https://techjourneyman.com/blog/m1-ultra-vs-nvidia-rtx-3090/ Look at that updated graph which has less BS. It's never close in perf/watt. The BS part about apples graph was that they cut the graph short for the nvidia card (and bending the graph a bit at the end). The full graph still shows apple being way better per watt .
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It's not, because Apple purposefully lied on their marketing material. Letting a 3090 go on full blast brings it pretty much in line in perf/watt. Your 3090 will not massively thermal throttle after 30 minutes either, but the M1 Ultra will. So, yes, if you want to look good on pointless benchmarks, a M1 ultra ran for 1 minute is more efficient than a downclocked 3090.
How do you think Nvidia got Samsung’s 8nm process to be just as power efficient as TSMC’s 5nm node?
Don't claim it just show/proof it by offering a chip for consumers that matches or better beats the metrics of Apples offerings.
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Nice followup to your link: https://chipsandcheese.com/p/arm-or-x86-isa-doesnt-matter . Personally I do not entirely buy it. Intel and AMD have had plenty of years to catch up to Apple's M-architecture and they still aren't able to touch it in efficiency. The PC Snapdragon chips AFAIK also offer better performance-per-watt than AMD or Intel, with laptops offering them often having 10-30% longer battery life at simila…
> Personally I do not entirely buy it. Intel and AMD have had plenty of years to catch up to Apple's M-architecture and they still aren't able to touch it in efficiency. The PC Snapdragon chips AFAIK also offer better performance-per-watt than AMD or Intel, with laptops offering them often having 10-30% longer battery life at similar performance. Do not conflate battery life with core efficiency. If you want to measu…
Higher wattage gives diminishing returns. Chips will run higher wattage under full load just to eke out a marginal improvement in performance. Therefore efficiency improves if the manufacturer chooses to limit the chip rather than pushing it harder.
Test efficiency using whatever task the chip will be used for. For most ultralight laptops, that will be web browsing etc. so the m1 MacBook/snapdragon results are valid for typical users. Maybe your workload hammers the CPU but that doesn't make it the one true benchmark.
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Yes, Intel/AMD cannot match Apple in efficiency. But Apple cannot beat Intel/AMD in single-thread performance. (Apple marketing works very hard to convince people otherwise, but don't fall for it.) Apple gets very, very close, but they just don't get there. (As well, you might say they get close enough for practical matters; that might be true, but it's not the question here.) That gap, however small it might be for…
> Apple has a max-efficiency design that's excellent for personal computing. Intel/AMD have aging max-performance designs that do beat Apple at absolute peak... Can you explain then, how come switching from Intel MBP to Apple Silicon MBP feels like literally everything is 3x faster, the laptop barely heats up at peak load, and you never hear the fans? Going back to my Intel MBP is like going back to stone age computi…
My understanding of it is that Apple Silicon's very very long instruction pipeline plays well with how the software stack in MacOS is written and compiled first and foremost.
Similarly that the same applications take less RAM in MacOS than even in Linux often even because at the OS level stuff like garbage collection are better integrated.
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There are just so many confounding factors that it's almost entirely impossible to pin down what's going on. - M-series chips have closely integrated RAM right next to the CPU, while AMD makes do with standard DDR5 far away from the CPU, which leads to a huge latency increase - I wouldn't be surprised if Apple CPUs (which have a mobile legacy) are much more efficient/faster at 'bursty' workloads - waking up, doing so…
Zen 5 also seems to have a bit of a underperforming memory subsystem, from what I can gather. Hardware Unboxed just did an interesting video[1] comparing gaming performance of 7600X Zen 4 and 9700X Zen 5 processors, and also the 9800X3D for reference. In some games the 9700X Zen 5 had a decent lead over the Zen 4, but in others it had exactly the same performance. But the 9800X3D would then have a massive lead over t…
They're still good benchmarks IMO because they represent a "real workload" but to understand why the 9800X3D performs this much better you'd want some metrics on CPU cache misses in the processors tested.
It's often similar to hyperthreading -- on very efficient sofware you actually want to turn SMT off sometimes because it causes too many cache evictions as two threads fight for the same L2 cache space which is efficiently utilized.
So software having a huge speedup from a X3D model with a ton of cache might indicate the sofware has a bad data layout and needs the huge cache because it keeps doing RAM round trips. You'd presumably also see large speedups in this case from faster RAM on the same processor.
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Yes they are, but only one of those is at all affected by the choice of ISA. If modern AMD chips are better at race-to-sleep than an Apple M1 and still get worse battery life then the problem is clearly not x86-64.
Does anyone care about blaming / lauding an ISA without any connection to the actual devices that people use? Performance and battery life are lived experiences. There’s probably some theoretical hyper optimization where 6502 ISA is just as good as ARM, but does it matter?
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I mean at 2GHz, and 2/3c, the signal travels about 10cm in 1 clock cycle. So it's not negligible, but I suspect it has much more to do with signal integrity and the transmission line characteristics of the data bus. I think since on mobile CPUs, the RAM sits right on top of the SoC, very likely the CPUs are designed with a low RAM latency in mind.
I think the m chips have much wider databus so bandwith is much higher as well as lower latency?
I'm curious how that is; in practice it "feels" like my 9950x is much more efficient at "move tons of RAM" tasks like a duckDB workload above a M4.
But then again a 9950x has other advantages going on like AVX512 I guess?
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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 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.