Microsoft this week finally released a version of Windows 10 on Arm that supports x86-64 (x64) emulation to members of the Windows Insider program. The software giant says that the preview version of Windows 10 on Arm supports any x64 app whether they come from the Microsoft Store or any other source.
Members of Microsoft's Windows Insider program with PCs powered by Qualcomm's Snapdragon (or any other) ARM64/Armv8 system-on-chips (SoCs) who want to try the new version of Windows on Arm with x64 emulation should download the Windows 10 Insider Preview Build 21277 (RS_PRERELEASE) from the Dev Channel.
To get decent app performance, users will also need to install a proper x64 driver for their Qualcomm Adreno GPUs, which is currently available only for Samsung's Galaxy Book S, Lenovo's Flex 5G, and Microsoft's Surface Pro X (more information and links here). Also, to support running both ARM64 and x64 C++ applications simultaneously, Microsoft advises installing a preview version of the ARM64 C++ redistributable.
Microsoft does not reveal any information about its x64 emulator's expected performance for Armv8 processors, so it is unclear whether the software is good enough for demanding applications like Adobe's Photoshop, or is mostly aimed at things like browsers. It is also unclear how stable the emulator is. Meanwhile, the software giant recommends developers support their apps natively on ARM64 and has been providing appropriate tools — Windows SDK and Visual Studio — since 2017.
Microsoft has been actively trying to bring Arm SoCs to the Windows PC space for almost a decade. Initially, the company wanted to offer an alternative to Apple's iPad. It released its Windows RT operating system in 2012, but the platform has never been popular, and Microsoft essentially canned the project in 2015 by axing its own Windows RT devices. The second attempt — sometimes called always-connected personal computers (ACPS) — was unveiled by Microsoft and Qualcomm in 2017. Instead of bringing an alternative to something on the market already, the two companies focused on a unique value proposition that Snapdragon SoCs can provide: long battery life and always-on connectivity.
In addition to launching an x64 emulator for Armv8 SoCs, Microsoft also plans to release a number of its programs, including Microsoft Teams, compiled and optimized specifically for Arm SoCs. Furthermore, Microsoft is also expanding its App Assure program to include Windows 10 on Arm 64-bit devices to guarantee that custom software designed for particular customers would work on all Windows 10 platforms no matter which processor or SoC they use.