Microsoft have brought some of DirectX 12's performance-improving parts to Windows 7, ending years of DX12 being exclusive to Windows 10. World Of Warcraft is the first game to benefit from DX12 features including multithreading on Windows 7, and Microsoft say they're working with several other developers to juice their games up on Windows 7 too. This isn't the full DirectX 12 package and doesn't bring all the performance improvements of DX12, to be clear, but it is a nice little bonus. Having the exclusive lock on DX12 was one of the main ways Microsoft nudged people towards Windows 10, after all.
Microsoft's Graphics Team program manager, Jianye Lu, explained in Tuesday's blog post that Blizzard asked Microsoft to throw them a bone after boosting World Of Warcraft's performance with DX12 on Windows 10.
"At Microsoft, we make every effort to respond to customer feedback, so when we received this feedback from Blizzard and other developers, we decided to act on it," Lu said. "Microsoft is pleased to announce that we have ported the user mode D3D12 runtime to Windows 7. This unblocks developers who want to take full advantage of the latest improvements in D3D12 while still supporting customers on older operating systems."
While hard numbers are elusive/impossible, 25% of respondents to Steam's hardware and software survey were still using on Windows 7 as of February 2019. That's a fair indicator that yeah, W7 is still pretty big.
Windows 7's DX12 features are now supported in World Of Warcraft as of Tuesday's update 8.1.5. Players will need the appropriate hardware to benefit from this, of course, but it's hardly bleeding-edge tech.
Lu also noted that Microsoft "are currently working with a few other game developers to port their D3D12 games to Windows 7," so we should see improved performance in more games too. The full DirectX 12 on Windows 10 also brings a number of optimisations that cut overhead, and these are not in the W7 iteration, but getting stuff like multithreading is nice. Even if Microsoft do plan to end Windows 7 support in January 2020.
At the same time, it is frustrating to see Microsoft bring handy performance-boosting features to Windows 7 nearly four years after DX12 launched with Windows 10. If Windows 7 had supported even this subset of features years ago, it would've given developers way more incentive to support them - helping players on both Windows 7 and 10. Microsoft declare with every big new DirectX launch that this will bring big performance improvements so we better get onboard, but it takes years for those optimisations to be commonly-used because it's just not worth it when only people with the newest hardware and software would benefit.
So this is nice and all, but would've been far nicer in 2015.