Microsoft is giving Windows on Arm a meaningful boost. An update to Prism, its x86 emulation engine, is rolling out to Windows 11 on Arm devices and quietly fixing one of the platform’s biggest pain points: compatibility with modern, CPU-intensive software.
With this update, Prism can now emulate several advanced x86 instruction set extensions — including AVX and AVX2, plus BMI, FMA, F16C and others. These extensions are heavily used by creative tools and modern games, which often refuse to install or run at all if they don’t detect them on the CPU.
For users of Snapdragon X–powered laptops and other Windows on Arm devices, that means more apps that just wouldn’t run before now install and work under emulation.
What Prism actually does on Windows on Arm
Prism is the core x86 emulation layer in Windows on Arm. Its job is to ensure that traditional Windows apps compiled for x86_64 (Intel/AMD) can still run on ARM64 hardware.
It does this by translating x86 instructions to Arm64 on the fly as the app executes. Ideally, the user doesn’t notice any difference: they double-click the app, it opens, and behaves like it would on an x86 machine — even if there’s no native Arm version.
The catch, until now, was that many demanding apps and games rely on extended instruction sets like AVX/AVX2. If those weren’t available, installers would fail with CPU requirement errors, or the app would crash at startup.
That’s the gap this Prism update targets.
Why AVX/AVX2 and friends matter so much
The new Prism version expands the set of CPU features that are emulated and exposed to x86 apps, including:
- AVX and AVX2 – Advanced vector extensions widely used in video, audio, physics, compression and many modern game engines.
- BMI – Bit manipulation instructions used for efficient low-level operations.
- FMA (Fused Multiply-Add) – Crucial for high-performance numeric workloads.
- F16C – Faster conversions between 32-bit and 16-bit floating-point formats, relevant in graphics and ML pipelines.
These features are not guaranteed on every Windows PC, but they’re common enough that a lot of software assumes they’re there — especially pro-grade creative tools and recent games.
The practical impact:
- Apps that previously refused to install now pass CPU checks and install normally.
- Software that hard-requires AVX/AVX2 can now run under emulation on Windows on Arm.
Microsoft uses Ableton Live 12 as a concrete example. Before the update, trying to install Ableton Live on Windows on Arm would fail because the installer requires AVX. After the Prism update, the app installs and runs under emulation, while a full native Arm version is expected next year.
For power users, this closes one of the biggest compatibility gaps for creative workloads and gaming on Arm laptops.
Who gets the Prism update — and how apps are affected
The new Prism capabilities are rolling out to all Windows on Arm devices running Windows 11, version 24H2 or later.
Behavior differs slightly depending on the app type:
- For 64-bit x86 apps, the expanded CPU feature set is enabled by default.
- For 32-bit apps, it is disabled by default but can be manually enabled through compatibility settings.
From the user’s perspective, there’s no separate download: it arrives as part of Windows Update. Once installed, x64 applications that previously hit a hard wall on CPU requirements may start working without any extra steps.
The biggest winners are:
- Creative professionals using DAWs, video editors, 3D and photo tools that relied on AVX/AVX2.
- PC gamers who found that certain modern titles simply would not launch on Arm because of missing CPU features.
- Advanced users running niche or older x86 software with strict CPU checks.
Performance will still depend on emulation overhead and each app’s behavior, but the binary “won’t run at all” scenario becomes less common.
Windows on Arm: from “nice idea” to viable option
When Windows on Arm first appeared, it felt like a promising but rough experiment: limited hardware, weak performance and patchy app support. The story is changing:
- Arm laptops like those based on Snapdragon X have made big strides in CPU/GPU performance and battery life.
- Many mainstream apps now ship native Arm64 builds.
- Prism has replaced the older emulation layer with better performance and broader compatibility.
This update is important precisely because it addresses a subtle but painful issue: apps that didn’t just run slower, but didn’t run at all due to missing instructions.
There will always be a performance gap between native and emulated code, but if Windows on Arm can reach the point where the vast majority of x86 software at least runs — and more and more of the everyday stack is native — it becomes a realistic alternative for many users, not just early adopters.
What’s next for Prism and Windows on Arm
Microsoft states it is committed to continuing to enhance Prism, both in terms of the instruction sets it supports and overall performance under emulation. In parallel, it continues to encourage developers to ship native Arm builds for Windows, especially now that Arm-based Copilot+ PCs are a major strategic bet.
In the short term, users gain something very tangible:
- Fewer “your CPU doesn’t meet requirements” errors.
- More games that at least start (even if performance will vary).
- More pro apps that behave like they do on a traditional x86 laptop.
In the long term, if publishers keep delivering native Arm versions — as Ableton plans to do — Prism will gradually shift from “critical compatibility crutch” to “safety net for legacy and edge cases”.
Until that happens, updates like this one are exactly what Windows on Arm needed: less fine print, fewer asterisks, and a stronger case that Arm laptops running Windows are finally ready for real-world workloads, not just demos.
source: Microsoft