Khronos Group Clears Confusion, Confirms Vulkan Multi-GPU Support For Windows 7/8.1

Late last week, news came across the wire that Khronos Group’s Vulkan API would not be supporting multi-GPU configurations on legacy operating systems like Windows 7 and Windows 8.1. This determination was made based on a slide that came from a Khronos Group presentation from GDC 2017.

In the slide deck, it was stated that native multi-GPU support for AMD CrossFire and NVIDIA SLI was reliant on the Windows Display Driver Model (WDDM) being set to Linked Display Adapter (LDA) mode. It was assumed that the LDA mode was exclusive to WDDM 2.0, thus making multi-GPU support available only to gamers running Windows 10.

Well, you know what they say when you assume things. Khronos Group reached out to us today to clear the air on multi-GPU support on Windows operating systems and to assure us that those running Windows 7 or Windows 8.1 will still be able to get their CrossFire or SLI gaming fix.

“The good news is that the Vulkan multi-GPU specification is very definitely NOT tied to Windows 10,” wrote the Vulkan Working Group. “It is possible to implement the Vulkan multi-GPU extension on any desktop OS including Windows 7, 8.X and 10 and Linux.” The Vulkan Working Group also went to state that the slide on LDA mode “was not a very clear statement that has caused some confusion.”

To clarify, it has provided the following guidelines for multi-GPU support and LDA with the Vulkan API:

• The use of WDDM is referring to the use of Vulkan multi-GPU functionality on Windows. On other OS, WDDM is not necessary to implement the Vulkan multi-GPU extension.
• The use of LDA mode can make implementing Vulkan multi-GPU functionality easier, and will probably be used by most implementations on Windows, but it is not strictly necessary.
• If an implementation on Windows does decide to use LDA mode, it is NOT tied to Windows 10. LDA mode has been available on many versions of Windows, including Windows 7 and 8.X.

In other words, you can put down your pitchforks and Molotov cocktails. If you want to go old school and game on Windows 7 and Windows 8.1, rest assured that you’re multi-GPU fix will not be stymied by Vulkan.