If you're rocking Intel's new Kaby Lake CPU or AMD's super-fast Ryzen processors and running an older operating system like Windows 7 or Windows 8.1, well - you're out of luck. Microsoft no longer supports operating systems older than Windows 10 (because it's been out for so long now).
Microsoft is now gimping Kaby Lake and Ryzen CPUs on Windows 7/8.1, effectively forcing you to upgrade to Windows 10 - as they've thrown a processor check into the latest Windows Update for W7/8.1 - sneaky. This update prevents Kaby Lake and Ryzen CPU owners from downloading updates, with an error message that reads: "Your PC uses a processor that isn't supported on this version of Windows".
This doesn't mean Microsoft is completely throwing Windows 7 or Windows 8.1 away, it's only for the newer Kaby Lake and Ryzen CPU architectures. Microsoft is still issuing security patches to its older operating systems, but if you're rocking a new Kaby Lake-based Core i7-7700K or Ryzen 7 1800X, you're done. Sorry, with no love, Microsoft.