Microsoft has integrated early support for Intel's Advanced Performance Extensions into Windows 11 Insider Preview build 29695. Discovered by enthusiast Xeno, the experimental Rubidium codebase includes a dormant toggle that asks to restart the system and let the OS use APX for improved performance. The feature is expected to arrive broadly in a future release such as Windows 11 27H2. [1][2][3]
APX expands the standard x86-64 architecture by doubling general-purpose registers from 16 to 32, allowing compilers to retain more values directly in the processor. Intel says optimized code features 10% fewer loads, over 20% fewer stores, and about 10% fewer overall instructions. The instruction set also adds three-operand instructions, PUSH2 and POP2 operations, conditional handling, and a 64-bit direct-jump instruction to cut down on memory transfers and branch mispredictions. [1][2]
Enabling the preview toggle currently does nothing because no consumer silicon supports the technology yet. Intel intends to debut APX in the server market with upcoming Diamond Rapids Xeon processors before eventually extending it to consumer chips like Nova Lake. Developers can target the architecture simply by recompiling their software, though tangible gains will depend on upcoming hardware benchmarks. [1][2]
