Microsoft has added an Intel APX performance toggle to an experimental Windows 11 build, getting ahead of consumer processors that support it.
According to Hardware Busters, enabling it on existing PCs offers about the same performance boost as polishing the case. The setting appears in Experimental Build 29695, based on Microsoft’s developing Rubidium platform. It sits under System’s advanced settings and requires a restart.
Intel’s Advanced Performance Extensions expand x86-64 general-purpose registers from 16 to 32, helping compiled software keep working data inside the processor.
APX introduces three-operand instruction forms, conditional comparisons and instructions that avoid unnecessary status-flag updates.
Chipzilla’s SPEC CPU 2017 simulations suggested roughly 10 per cent fewer loads, more than 20 per cent fewer stores and around 10 per cent fewer instructions. Those figures describe recompiled workloads in simulation, but they don’t confirm an equivalent speed increase in Windows.
Operating-system support is necessary because Windows must preserve the additional registers when switching between threads. GCC 15 already supports APX compilation. Intel’s Nova Lake is expected to bring the feature to desktops.
Microsoft has given no firm date for the toggle’s arrival in a stable Windows release.
