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People keep repeating that Zen4 and M1 are close in efficiency but what is the source with actual benchmarks and power measurements?

At any rate, using single points to compare energy efficiency isn't a good comparison, unless either the performance or power consumption of the data points comparable. Like, the M1's little cores are 3-5x even more efficient when operating in an incomparable power class, and Apple's own marketing graphs show the M1's max efficiency is also well below its max performance [1]

Those perf/power curves are the basis of actually useful comparisons; has anyone plotted some outside of marketing materials? It might even be possible under Asahi.

[1] https://www.apple.com/newsroom/2021/10/introducing-m1-pro-an...



> but what is the source with actual benchmarks and power measurements?

Every notebookcheck.net review. For example https://www.notebookcheck.net/AMD-Ryzen-7-6800U-Efficiency-R...

They also do the same to a lot more laptops they test.

Look at the multi-core results, Zen3+ comes pretty close.

Also the single thread result shows what GP said: AMD CPU drains too much power at idle.


Their results are invalid because they used Cinebench. Cinebench uses Intel Embree engine which is hand optimized for x86, not ARM instructions. In addition, Cinebench is a terrible general purpose CPU benchmark.[0]

Imagine if you're testing how energy efficient an EV and a gas car is. But you only run the test in the North pole, where the cold will make the EV at least 40% less efficient. And then you make a conclusion based solely on that data for all regions in the world. That's what using Cinebench to compare Apple Silicon and x86 chips is like.

[0] https://www.reddit.com/r/hardware/comments/pitid6/eli5_why_d...


Cinebench/4D does have "hand-optimized" ARM instructions. It would be a disaster for the actual product if it didn't. That's what makes it interesting as a benchmark: that there's a real commercial product behind it and a company interested in making it as efficient as possible for all customer CPUs, not just benchmarking purposes.

Albeit for later releases this is less true since most customers have switched to GPUs...


Cinebench/4D does have "hand-optimized" ARM instructions.

It doesn't. As far as I know, everything is translated from x86 to ARM instructions - not direct ARM optimization.

Cinema4D is a niche software within a niche. Even Cinema4D users don't typically use CPU renderer. They use the GPU renderer.

The reason Cinebench became so popular is because AMD and Intel promote it heavily in their marketing to get nerds to buy high core count CPUs that they don't need.


Generally you see this in the lower class chips that aren’t overclocked to within an inch of instability. It’s not uncommon to see a chip that uses 200w to perform 10% worse at 100w, or 20% worse at 70w.

I can’t be bothered to chase down an actual comparison, but usually you’ll see something along those lines if you compare the benchmarks for the top tier chip with a slightly lower tier 65w equivalent.



Cheers for the link - if I read right there’s a cliff around 100w where power use goes way up for extremely marginal improvements.

Below 100w it’s more linear, but that might depend on undercoating and the like as well.




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