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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 high

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 1y ago
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.
- wordofx 1y ago
  [flagged]
- chasil 1y ago
  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.
  - daeken 1y ago
    There's no AArch32 or Thumb support (A32/T32) on M-series chips. AArch64 (technically A64) is the only supported instruction set. Fun fact: this makes it impossible to run Mario Kart 8 via virtualization on Macs without software translation, since it's A32. How much that does for efficiency I can't say, but I imagine it helps, especially given just how damn easy it is to decode.
    - averne_ 1y ago
      It actually doesn't make much difference: https://chipsandcheese.com/i/138977378/decoder-differences-a-drop-in-the-bucket https://chipsandcheese.com/i/138977378/decoder-differences-a...
      - daeken 1y ago
        Oh wow, I need to dig way deeper into this but wonderful resource - thanks!
      - chasil 1y ago
        I had not realized that Apple did not implement any of the 32-bit ARM environment, but that cuts the legs out of this argument in the article: "In Anandtech’s interview, Jim Keller noted that both x86 and ARM both added features over time as software demands evolved. Both got cleaned up a bit when they went 64-bit, but remain old instruction sets that have seen years of iteration." I still say that x86 must run two FPUs all the time, and that has to cost some power (AMD must run three - it also has 3dNow). Intel really couldn't resist adding instructions with each new chip (MMX, PAE for 32-bit, many more on this shorthand list that I don't know), which are now mostly baggage.
        theevilsharpie 1y ago
        > I still say that x86 must run two FPUs all the time, and that has to cost some power (AMD must run three - it also has 3dNow). Legacy floating-point and SIMD instructions exposed by the ISA (and extensions to it) don't have any bearing on how the hardware works internally. Additionally, AMD processors haven't supported 3DNow! in over a decade -- K10 was the last processor family to support it.
- Fluorescence 1y ago
  > 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-14-Core-vs-AMD-Ryzen-AI-Max+-395 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-m4-pro-gpu-20-core https://nanoreview.net/en/gpu-compare/radeon-8060s-vs-apple-...
  - aurareturn 1y ago
    Where are you getting M4 die sizes from? M1 Pro is ~250mm2. M4 Pro likely increased in size a bit. So I estimated 300mm2. There are no official measurements but should be directionally correct. AMD's multicore passmark score is more than 40% higher. It's an out of date benchmark that not even AMD endorses and the industry does not use. Meanwhile, AMD officially endorses Cinebench 2024 and Geekbench. Let's use those. The AMD is an older fab process and does not have P/E cores. What are you measuring? Efficiency. Fab process does not account for the 3.65x efficiency deficit. N4 to N3 is roughly ~20-25% more efficient at the same speed. The P/E design choice gives different trade-offs e.g. AMD has much higher average single core perf. Citation needed. Further more, macOS uses P cores for all the important tasks and E cores for background tasks. I fail to see why even if AMD has a higher average ST would translate to better experience for users. 14.8 TFLOPS vs. M4 Pro 9.2 TFLOPS. TFLOPs are not the same between architectures. 19% higher 3D Mark Equal in 3DMark Wildlife, loses vs M4 Pro in Blender. 34% higher GeekBench 6 OpenCL OpenCL has long been deprecated on macOS. 105727 is the score for Metal, which is supported by macOS. 15% faster for M4 Pro. The GPUs themselves are roughly equal. However, Strix Halo is still a bigger SoC.
    - 1y ago

aurareturn 1y ago

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.

wordofx 1y ago
[flagged]
chasil 1y ago
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.
- daeken 1y ago
  There's no AArch32 or Thumb support (A32/T32) on M-series chips. AArch64 (technically A64) is the only supported instruction set. Fun fact: this makes it impossible to run Mario Kart 8 via virtualization on Macs without software translation, since it's A32. How much that does for efficiency I can't say, but I imagine it helps, especially given just how damn easy it is to decode.
  - averne_ 1y ago
    It actually doesn't make much difference: https://chipsandcheese.com/i/138977378/decoder-differences-a-drop-in-the-bucket https://chipsandcheese.com/i/138977378/decoder-differences-a...
    - daeken 1y ago
      Oh wow, I need to dig way deeper into this but wonderful resource - thanks!
    - chasil 1y ago
      I had not realized that Apple did not implement any of the 32-bit ARM environment, but that cuts the legs out of this argument in the article: "In Anandtech’s interview, Jim Keller noted that both x86 and ARM both added features over time as software demands evolved. Both got cleaned up a bit when they went 64-bit, but remain old instruction sets that have seen years of iteration." I still say that x86 must run two FPUs all the time, and that has to cost some power (AMD must run three - it also has 3dNow). Intel really couldn't resist adding instructions with each new chip (MMX, PAE for 32-bit, many more on this shorthand list that I don't know), which are now mostly baggage.
      - theevilsharpie 1y ago
        > I still say that x86 must run two FPUs all the time, and that has to cost some power (AMD must run three - it also has 3dNow). Legacy floating-point and SIMD instructions exposed by the ISA (and extensions to it) don't have any bearing on how the hardware works internally. Additionally, AMD processors haven't supported 3DNow! in over a decade -- K10 was the last processor family to support it.
Fluorescence 1y ago
> 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-14-Core-vs-AMD-Ryzen-AI-Max+-395 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-m4-pro-gpu-20-core https://nanoreview.net/en/gpu-compare/radeon-8060s-vs-apple-...
- aurareturn 1y ago
  Where are you getting M4 die sizes from? M1 Pro is ~250mm2. M4 Pro likely increased in size a bit. So I estimated 300mm2. There are no official measurements but should be directionally correct. AMD's multicore passmark score is more than 40% higher. It's an out of date benchmark that not even AMD endorses and the industry does not use. Meanwhile, AMD officially endorses Cinebench 2024 and Geekbench. Let's use those. The AMD is an older fab process and does not have P/E cores. What are you measuring? Efficiency. Fab process does not account for the 3.65x efficiency deficit. N4 to N3 is roughly ~20-25% more efficient at the same speed. The P/E design choice gives different trade-offs e.g. AMD has much higher average single core perf. Citation needed. Further more, macOS uses P cores for all the important tasks and E cores for background tasks. I fail to see why even if AMD has a higher average ST would translate to better experience for users. 14.8 TFLOPS vs. M4 Pro 9.2 TFLOPS. TFLOPs are not the same between architectures. 19% higher 3D Mark Equal in 3DMark Wildlife, loses vs M4 Pro in Blender. 34% higher GeekBench 6 OpenCL OpenCL has long been deprecated on macOS. 105727 is the score for Metal, which is supported by macOS. 15% faster for M4 Pro. The GPUs themselves are roughly equal. However, Strix Halo is still a bigger SoC.
  - 1y ago