Microsoft improves its Prism x86-on-ARM emulator

The current version of Windows on ARM contains Prism, Microsoft’s emulator that allows x86-64 code to run on ARM processors. While it was already relatively decent on the recent Snapdragon X platform, it could still be very hit-or-miss with what applications it would run, and especially games seemed to be problematic. As such, Microsoft has pushed out a major update to Prism that adds support for a whole bunch of extensions to the x86 architecture.

This new support in Prism is already in limited use today in the retail version of Windows 11, version 24H2, where it enables the ability to run Adobe Premiere Pro 25 on Arm. Starting with Build 27744, the support is being opened to any x64 application under emulation. You may find some games or creative apps that were blocked due to CPU requirements before will be able to run using Prism on this build of Windows.

At a technical level, the virtual CPU used by x64 emulated applications through Prism will now have support for additional extensions to the x86 instruction set architecture. These extensions include AVX and AVX2, as well as BMI, FMA, F16C, and others, that are not required to run Windows but have become sufficiently commonplace that some apps expect them to be present. You can see some of the new features in the output of a tool like Coreinfo64.exe.
↫ Amanda Langowski and Brandon LeBlanc on the Windows Blog

Hopefully this makes running existing x86 applications that don’t yet have an ARM version a more reliable affair for Windows on ARM users.