The change is actually very simple. When the March 2017 Windows update rolled out (Post Ryzen 7 launch), users spotted two new new function in ‘wuaueng.dll’ - “IsCPUSupported(void)” and “IsDeviceServiceable(void)”. If the CPU is either Ryzen or Kaby Lake, the respective checks block Windows updates. The custom-made patch alters these checks and reassures Windows 7 and Windows 8 that these are in fact supported processors. Once done, the usual security updates download as per normal.
The patch itself was put together by a chap named Zeffy, and they’ve uploaded it to GitHub. All you need to do is download the patch and follow some fairly simple instructions on GitHub. The downside is that you’ll need to reapply this patch when the ‘wuaueng.dll’ is updated. This may be often, it may be never, but it’s something to keep in mind.