Intel Core i9 12900K "Alder Lake" AVX-512 On Linux
Written by Michael Larabel in Processors on 7 November 2021. Page 2 of 2. 88 Comments

Sure enough, right away we see AVX-512 actually working on the Core i9 12900K in this P-core-only configuration... With the first test, the P-cores with AVX-512 was nearly enough to match the stock configuration (P + E cores enabled, sans AVX-512).

But the power consumption shot higher when engaging AVX-512... We still are seeing some scheduling oddities under Linux (current lack of Thread Director optimizations for Linux) and other odd behavior at times, such as here with the P-core-only configuration consuming more power than the stock configuration with E cores also running.

A Noctua NH-U9S with dual fan configuration was used for cooling the Core i9 12900K and keeping it under control even with AVX-512 enabled.

For workloads/codebases well optimized for AVX-512, it was possible to see the i9-12900K with AVX-512 outperform the full stock configured i9-12900K with 24 threads.

But it comes at the cost of even higher power consumption.

So from the quick weekend testing, AVX-512 on Alder Lake at least for now is indeed possible when limiting the configuration to P cores... It will be interesting to see if this remains the case or future system firmware updates remove the ability to enable AVX-512 or later steppings of Alder Lake processors do physically fuse off AVX-512 as Intel originally stated. At least until that happens, we'll keep experimenting.

If you enjoyed this article consider joining Phoronix Premium to view this site ad-free, multi-page articles on a single page, and other benefits. PayPal tips are also graciously accepted. Thanks for your support.

Related Articles
About The Author
Author picture

Michael Larabel is the principal author of and founded the site in 2004 with a focus on enriching the Linux hardware experience. Michael has written more than 20,000 articles covering the state of Linux hardware support, Linux performance, graphics drivers, and other topics. Michael is also the lead developer of the Phoronix Test Suite, Phoromatic, and automated benchmarking software. He can be followed via TwitterLinkedIn,> or contacted via

Trending Linux News