Intel is planning to disable AVX-512 support across all 12th Gen Alder Lake-S processors next week. The chipmaker is going to release a microcode update via a BIOS release, completely blocking AVX3 support, even when the efficiency cores are disabled on the Alder Lake SKUs. Earlier, board partners were able to enable the wider instruction set to significantly boost floating-point performance in supported applications.
Now, Intel is pressuring its partners to disable the feature, most likely to make its upcoming Sapphire Rapids-X processors look more attractive to professionals and creators as those applications benefit the most from AVX-512. The firmware update is slated to roll out next week (at CES), after which all Z690 motherboards will stop supporting the instruction set on all configurations.
Furthermore, AVX2 instructions are also limited by the x51 multiplier. This implies that the Core i9-12900K is able to hit its rated boost clock of 5.2GHz in applications like Cinebench, it is 100MHz lower in LinpackXtreme as the latter takes advantage of AVX2. Even if you set the CPU clock to static in the BIOS, remove all performance limits and ensure sufficient cooling, the CPU throttles still itself down to 5.1 GHz when running AVX2 supported instructions.
Of course, there are community-created patches to re-enable AVX-512, it still makes the decision anti-consumer. We’ll have to wait and see what Intel’s official reasoning for disabling the instruction set is.
Via: Igor’s Lab