Intel Core i9 12900K "Alder Lake" AVX-512 On Linux

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.