YouTubes Thirty IR has shared a new video, showing Metro Exodus running in 8K resolution, 7680×4320, on Extreme settings. In order to achieve something like that, Thirty IR used two NVIDIA Titan RTX graphics cards in SLI and used the DirectX 11 API (as SLI is not currently supported in DX12).
Source: N4G PC Here is Metro Exodus running in 8K/Extreme Settings with 60fps on two NVIDIA Titan RTX GPUs in DX11