Starting with Intel’s Kaby Lake (7th Gen) and AMD’s Ryzen 1000 series, support for Windows 7 on newer CPUs was officially discontinued. Even if you install Windows 7, Windows Update will often scan your hardware and declare that your processor is not supported, blocking critical security updates. The Cause: Microsoft declared that "Windows 7 is designed to work with today's multi-core processors," but optimization for newer architectures was reserved for Windows 10.
Newer computers often lack the legacy drivers (USB 3.x, NVMe, and SATA) needed for a standard Windows 7 installation. Installing WINDOWS 7 On An AMD RYZEN PC windows 7 unsupported hardware fix