It's been a long time since we've had to worry about CPU / OS incompatibilities. In fact, the last time it was an issue was the shift from x86 to x64, but that was largely transparent to consumers thanks to AMD and its x86-64 specification, which was later adopted by Intel. Now, with Windows 7 having just entered its extended support phase, Microsoft has taken the opportunity to drop the news that only Windows 10 will be supported on upcoming CPUs.
Terry Myerson, Microsoft's executive VP for the Windows and Devices Group, explained the move over on the official Windows blog:
Windows 7 was designed nearly 10 years ago before any x86/x64 SOCs existed. For Windows 7 to run on any modern silicon, device drivers and firmware need to emulate Windows 7's expectations for interrupt processing, bus support, and power states — which is challenging for WiFi, graphics, security and more.
Myerson goes on to mention that because driver vendors have to keep accommodating Windows 7 in updates and new software, it makes it difficult to push forward with improvements on the more modern Windows 8.1 and 10.
As such, the company has made the decision to distance itself from older processors and platforms. Intel's Skylake refresh "Kaby Lake" will mark the start of this transition:
Going forward, as new silicon generations are introduced, they will require the latest Windows platform at that time for support. This enables us to focus on deep integration between Windows and the silicon, while maintaining maximum reliability and compatibility with previous generations of platform and silicon. For example, Windows 10 will be the only supported Windows platform on Intel's upcoming "Kaby Lake" silicon, Qualcomm's upcoming "8996" silicon, and AMD's upcoming "Bristol Ridge" silicon.
A list of supported devices will make an appearance in the near future and will help clear up what will work where:
In clarifying this policy, we are prioritizing transparency with enterprises on where to find the highest reliability and best supported Windows experience: Windows 10 on any silicon, Windows 7 on the down-level silicon it was designed for, or a device on the support list.
That doesn't mean Windows 7 will magically stop working on new CPUs and it's clear in the above statement Windows 10 won't suddenly explode on older hardware. It does however draw a line in the sand for Intel, Microsoft, AMD and other companies where we can finally make the proper transition to cutting-edge 64-bit silicon, rather than wallow with one foot in the 32-bit pool.
It was going to happen eventually and while it was a painful day when 16-bit applications stopped working in Windows, we all got over it eventually. And hey, there will always be Linux.