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Aurornisyesterday at 6:25 PM1 replyview on HN

True! But even if only 20% of the die area goes to AVX-512 in larger cores, that makes a big difference for high core count CPUs.

That would be like having a 50-core CPU instead of a 64-core CPU in the same space. For these cloud native CPU designs everything that takes significant die area translates to reduced core count.


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wtallisyesterday at 9:03 PM

You're still grossly overestimating the area required for AVX-512. For example, on AMD Zen4, the entire FPU has been estimated as 25% of the core+L2 area, and that's including AVX-512. If you look at the extra area required for AVX-512 vs 256-bit AVX2, as a fraction of total die area including L3 cache and interconnect between cores, it's definitely not going to be a double digit percentage.