We previously reported that Intel’s code in the openDNN project hinted at Intel Core Ultra 400 processors codenamed Nova Lake supporting the AVX10 and AVX-512 instructions for the first time—the modern 512-bit SIMD extension useful for AI, multimedia, and demanding computations. Simultaneously, the cores of these CPUs were supposed to gain the APX extension. However, information from Intel has now cast doubt on both.
This month, data on Intel Nova Lake processors was added to the GCC 16 and LLVM/Clang 22 compilers, including the instruction sets these CPUs support. And among them, neither AVX10 nor AVX-512 is present. There is also no indication in the code that the cores of these processors would support the APX extension, which adds more general-purpose registers for better performance. Similarly, the recently updated Intel manual (the Intel Architecture Instruction Set Extensions and Future Features document, 59th edition) also does not mention APX and AVX10 for Nova Lake.
The probability is therefore increasing that the previous information was incorrect. Alternatively, there may have been a change of plans during development or during the debugging of the first chip samples—in theory, there is a possibility that support for these technologies is affected by unfixable errata (similar to, for example, the TSX extension in the past) and must therefore remain disabled in the serial production processors. That’s probably a less likely scenario however, if it is indeed confirmed that Nova Lake will not provide these extensions, it was most likely the plan from the beginning.
New x86 instruction set extensions
AVX10 are 512-bit SIMD instructions that also include support for AVX-512. They would thus bring higher performance in multimedia applications, for example. Intel abandoned AVX-512 during the transition to the hybrid architecture with E-Cores, but almost simultaneously these instructions made their way into AMD processors (in Zen 4 and Zen 5 architectures), where they were quite well received. Nova Lake was hoped to be the moment where both processor brands would finally support AVX-512.
- Tip: AVX-512 replaced by AVX10. Now for big.LITTLE CPUs as well
- Tip: Intel scraps 256bit AVX10. P-Core and E-Core to receive AVX-512
The APX extension is an enhancements that allow programs to use more general-purpose registers. Their limited number is one of the weaknesses of the x86 instruction set compared to newer architectures (today primarily ARM); because of this, programs must spend time moving working data to memory, whereas a larger number of registers would allow this to be avoided and allow code to be executed faster. APX technology therefore increases the number of general-purpose registers from 16 to 32, while maintaining backward compatibility. Programs that are not designed for APX will run as before (but with unchanged performance).
Is there still hope?
It is possible that this is lack of support is not yet final. Complete documentation for processors, including the mentioned manual, is sometimes released quite late. The possibility therefore remains that Intel is taking its time and has so far only published incomplete information. It could eventually supplement the above-mentioned documentation at a later stage and confirm support for APX and AVX10. The same could apply to support patches in the Clang and GCC projects; the company could still send a new version of the patches that would include APX and AVX10.
How likely this possibility is, is difficult to say. Support for AVX10 and APX in Nova Lake processor cores was discussed, for example, by the leaker appearing on the former Twitter under the nickname Jaykihn, who usually bases his information on non-public Intel documents and tends to have some of the best information about the company’s plans. However, this does not rule out the scenario that older documents indeed promised these new extensions, but support was cancelled by a later decision.
So for now, it’s probably not a closed matter yet, but if you are looking forward specifically to one of these technologies, it’s better to reckon with the possibility that it won’t be in Nova Lake processors after all and you will have to wait for it in some subsequent Intel processor generation.
Nova Lake processors will launch as Core Ultra 400, and their release is scheduled for the second half of 2026, so they are still about a year away.
Sources: Intel, ComputerBase, Phoronix, Jaykihn, InstLatX64, GCC
English translation and edit by Jozef Dudáš
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