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AMD boasts of Vulkan multi-GPU support in Strange Brigade - Graphics - News - HEXUS.net
DirectX 12 Explicit Multi-GPU Performance Review with Ashes of the Singularity | DirectX 12 Explicit Multi-GPU Performance Review with Ashes of the Singularity | GPU & Displays | OC3D Review
AMD+NVIDIA Multi-GPU DirectX12 Benchmark: R9 390X + GTX 970 in 'SLIFire' | GamersNexus - Gaming PC Builds & Hardware Benchmarks
Microsoft makes multi-GPU support easier for DX12 devs - Software - News - HEXUS.net
DX12 Enables Cross-SLI Between AMD and Nvidia GPUs