An overclocker has discovered a method to rapidly and simply distinguish between Intel’s twelfth Era Core ‘Alder Lake’ processors which have AVX-512 help disabled by microcode and may be re-enabled with an acceptable BIOS, in addition to Alder Lake chips which have their AVX-512 unit fused off bodily. All it’s a must to do is to search for a CPU with an previous Intel logotype on its built-in warmth spreader (IHS).
When Intel was on the point of launch its newest twelfth Era Core ‘Alder Lake’ CPUs final yr, it informed software program builders that its Golden Cove (P)erformance cores absolutely supported AVX-512 directions (identical to cores inside previous-generation CPUs), however Gracemont (E)fficiency cores didn’t. However because the launch was nearing, the corporate determined to disable AVX-512 help on P-cores to make sure total stability simply months earlier than launch, which is why a great deal of preliminary LGA1700 motherboards got here with microcode with enabled AVX-512 help. It induced plenty of confusion.
To disable AVX-512 for certain, Intel launched a brand new reference UEFI BIOS model (which serves as a basis for UEFI variations shipped by motherboard makers) that turned expertise off, however then some mainboard makers launched UEFI BIOSes that re-enabled AVX-512. Ultimately, to make sure that the suitable {hardware} unit can’t be activated, Intel started to bodily fuse off its AVX-512 module from Alder Lakes.
However there are a great deal of twelfth Era Core processors which have their AVX-512 unit intact and which may be activated. Overclocker Luumi (through VideoCardz) has found that these ‘fortunate’ Alder Lake CPUs with AVX-512 have Intel’s historic spherical ‘Intel Inside’-like circle logotype on the higher left aspect of their IHS. In contrast, the ‘unfortunate’ Alder Lake chips with AVX-512 fused off carry Intel’s fashionable sq. logotype on the identical a part of their IHS.
“Appears that almost all 2022 batched Alder Lake CPUs have AVX-512 disabled, so you might be higher off searching a 2021 batch CPU,” Luumi wrote. “Fortunately for us Intel left a mark to find out does the CPU help AVX-512 or not, by trying on the IHS. Each CPU that has a halo/circle marking on high of the phrase Intel on the IHS could have AVX-512 help, and all rectangle/sq. ish marking CPUs could have it disabled by Intel. So not less than with the Pentiums and different decrease finish fashions you’ll be able to simply stroll round in a retailer and take a look at the processor’s IHS from the small peek window and decide if it has AVX-512 or not.”
To activate AVX-512, you’ll nonetheless want an acceptable UEFI BIOS model, and an eventual replace will nearly definitely disable the expertise, however for those who want AVX-512 right here and now and no firmware updates are deliberate, this is probably not a problem.
AVX-512 directions are required for encoding/decoding, cryptography, scientific, and varied skilled purposes. Players and customers of normal purposes hardly want AVX-512, however for those who do, re-enabling it makes plenty of sense.