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Using AVX2 registers in 256 bit mode and AVX512 can slow down the program because the overheating protection will drop frequency when some heavy load AVX2 and AVX-512 instructions are used. Read this [https://lemire.me/blog/2018/09/07/avx-512-when-and-how-to-use-these-new-instructions/ Article for more informations]. This information should be added to the Wikipedia article. --[[Special:Contributions/91.89.138.29|91.89.138.29]] ([[User talk:91.89.138.29|talk]]) 22:53, 6 October 2019 (UTC)
:You're correct on it being the over-temp and TDP limits controlling this. Everyone is using the Gold 5120 as an example; it has a TDP of 105W. The data from that is meaningless by itself as it's already a very low power chip for the core count and clocks. A comparison vs. the 5117F (400MHz lower turbo and 200MHz lower base but 8W higher TDP) and the performance chip: 6132 (Base 2.6GHz / Turbo 3.7GHz, TDP 140W) which are both 14 cores released at the same time as the 5120 would probably show that heavy curve at 14 cores utilized evening out or disappearing. With heavy enough cooling (workstation with water cooling rather than regular low profile heat sink you'd slap on a 105W chip), the 140W chip can probably handle running all cores at the fixed frequency drop ratio of 300MHz without exceeding the turbo TDP (likely 180W or in that range) or with very little change at all cores utilized. It's impossible to tell though since everybody apparently took one set of results and jumped to conclusions without testing anything else. Pretty soon they'll probably start showing up cheap enough on eBay to do actual tests but it's understandable why people weren't rushing out to go buy multiple $1500-$2000 processors to get real results. I'm just basing this on how the whole thing actually works, and it doesn't take into account the number of cores used except as the basis for max turbo clock with that many cores and the offset. That's purely a power issue and unless somebody does the microcode rollback and write-out of the adjustable clock config bits on a motherboard that will enable overclock settings with this flipped on so the TDP can be set higher they won't get that data out of a 5120 by itself. --[[User:A Shortfall Of Gravitas|A Shortfall Of Gravitas]] ([[User talk:A Shortfall Of Gravitas|talk]]) 09:07, 18 July 2021 (UTC)
== AVX's three-operand format and instructions with general purpose registers in AVX2? ==
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