Deus Ex: Mankind Divided was released for Windows last August while Feral Interactive completed the Linux port in November. This action role-playing game is powered by the Dawn Engine and under Windows does feature Direct3D 11 and 12 renderer options. Under Linux there is only an OpenGL renderer. The NVIDIA Linux driver stack has supported Deus Ex: Mankind Divided since its November launch while in recent weeks there has been ongoing optimization work by Radeon developers to make this game more playable on their Gallium3D driver.
With 1080p low quality between the Windows D3D11 and D3D12 results the performance was fairly close. Unfortunately, however, it shows the Linux OpenGL performance being well behind. On the GeForce GTX 1060 under Linux it was delivering about 80% the performance and with the GTX 1080 was at roughly 60%.
When upping the tests to the high quality game settings, the GeForce GTX 1060 was around 80% the speed of the Windows results while the GTX 1080 was also closer to 80% this time.
Given the Linux results already lagging behind at 1080p, for this Deus Ex game test I didn't run it at 4K.