[DuckConference]

They're big, expensive chips with a focus on power efficiency. AMD and Intel's chips that are on the big and expensive side tend toward being optimized for higher power ranges, so they don't compete well on efficiency, while their more power efficient chips tend toward being optimized for size/cost.

If you're willing to spend a bunch of die area (which directly translates into cost) you can get good numbers on the other two legs of the Power-Performance-Area triangle. The issue is that the market position of Apple's competitors is such that it doesn't make as much sense for them to make such big and expensive chips (particularly CPU cores) in a mobile-friendly power envelope.

[aurareturn]

Per core, Apple’s Performance cores are no bigger than AMD’s Zen cores. So it’s a myth that they’re only fast and efficient because they are big.

What makes Apple silicon chips big is they bolt on a fast GPU on it. If you include the die of a discrete GPU with an x86 chip, it’d be the same or bigger than M series.

You can look at Intel’s Lunar Lake as an example where it’s physically bigger than an M4 but slower in CPU, GPU, NPU and has way worse efficiency.

Another comparison is AMD Strix Halo. Despite being ~1.5x bigger than the M4 Pro, it has worse efficiency, ST performance, and GPU performance. It does have slightly more MT.

[chasil]

Is it not true that the instruction decoder is always active on x86, and is quite complex?

Such a decoder is vastly less sophisticated with AArch64.

That is one obvious architectural drawback for power efficiency: a legacy instruction set with variable word length, two FPUs (x87 and SSE), 16-bit compatibility with segmented memory, and hundreds of otherwise unused opcodes.

How much legacy must Apple implement? Non-kernel AArch32 and Thumb2?

Edit: think about it... R4000 was the first 64-bit MIPS in 1991. AMD64 was introduced in 2000.

AArch64 emerged in 2011, and in taking their time, the designers avoided the mistakes made by others.

[Fluorescence]

> Despite being ~1.5x bigger than the M4 Pro

Where are you getting M4 die sizes from?

It would hardly be surprising given the Max+ 395 has more, and on average, better cores fabbed with 5nm unlike the M4's 3nm. Die size is mostly GPU though.

Looking at some benchmarks:

> slightly more MT.

AMD's multicore passmark score is more than 40% higher.

https://www.cpubenchmark.net/compare/6345vs6403/Apple-M4-Pro...

> worse efficiency

The AMD is an older fab process and does not have P/E cores. What are you measuring?

> worse ST performance

The P/E design choice gives different trade-offs e.g. AMD has much higher average single core perf.

> worse GPU performance

The AMD GPU:

14.8 TFLOPS vs. M4 Pro 9.2 TFLOPS.

19% higher 3D Mark

34% higher GeekBench 6 OpenCL

Although a much crappier Blender score. I wonder what that's about.

https://nanoreview.net/en/gpu-compare/radeon-8060s-vs-apple-...