Internal Microsoft documentation leaked over the years confirms that a project existed to port Windows XP to ARMv4 and ARMv5 architectures. Code-named internally as "NT/ARM," the project reached a working kernel and a command-line environment. However, it was cancelled around 2003 for three reasons:
: Because every instruction must be translated, performance is significantly slower than native hardware. It is often described as feeling like a "233MHz" processor from the late 90s. Windows RT vs. XP windows xp arm64 iso