Why does DX12 destroy performance in DXMD?

[fordongreeman]

Why does enabling DX12 destroy my performance in Deus Ex Mankind Divided?

I have two-way SLI GTX 1080 and after I enable DX12, my FPS drops to 25-35 even at 1920x1080.

 

[Dunlop0078]

Found this.

"To activate Multi-GPU DirectX 12 you are required to do the following: Within your Steam Library, right-click on Deus Ex: Mankind Divided. Select ‘properties’ from the context menu and navigate to the Beta tab. From the drop down menu, select dx12_mgpu_preview then close the window."

I also found that that game just does not have very good sli support in dx11 or dx12, but it should do better than what you are getting.

https://wccftech.com/deus-ex-mankind-divided-pc-patch-mgpu-dx12-official/