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I can launch the game with Crossfire enabled quite happily, although it doesn't get used of course since the game developers haven't added that.
Change the Doom profile to disable Crossfire if it is an issue for you, since it isn't going to benefit from it anyway.
Cool, thanks for the video. Do you know if crossfire support is in the pipeline? I've heard conflicting things about Vulkan and mGPU
Hi Matt - With the Vulkan patch is it possible to force another crossfire profile and see if there are any gains? Could try forcing one from a different Vulkan game, or just try the standard option of AFR or 1x1 and see if there is any scaling?
As mentioned above, CrossFire support in Vulkan can only be added by the developer. Existing DX11 CrossFire profiles will not work with Vulkan.
Thanks so much for the post OP. I was having this problem, completely unable to launch Doom in Vulkan mode. Every time I launched it, I would get a black screen and the game would hang. I tried many solutions but none worked. After reading this post, I tried disabling crossfire in the Doom profile specifically; it didn't work. However, when I disabled crossfire globally, the game finally launches in Vulkan mode! I tried turning crossfire back on globally and it hung again - it will only launch with it disabled globally. Thanks so much for your help.
GPU1: XFX R9 Fury Triple Dissipation
GPU2: Sapphire R9 Nano
CPU: Core i5 4690k @ 4.4Ghz
OS: Windows 8.1
RAM: 16GB DDR3
Monitor: 27 inch 3840x2160 Freesync IPS
Running 2 380x's, I have crossfire disabled in profile but enabled globally, and I can launch the game in Vulkan just fine. Only issue is it takes about 2 minutes to launch. A minute with nothing but Doom popping up in task manager, then another minute of a blank, black window. Then finally it goes fullscreen and the Bethesda logo appears.
So maybe if you guys are having trouble, just wait a couple minutes after trying to launch?