AMD only allows configurations of two AMD RX Vega graphics via mGPU in AMD Crimson ReLive 17.9.2 drivers, at least for now.

This past Thursday, new drivers, the AMD Crimson ReLive 17.9.2, were made available to users with AMD RX Vega graphics, which as a great novelty, allowed multi-GPU configurations. It seems that these drivers hide paranormal things, among others, that they do not support the configuration of four graphics cards in the same system, something curious, because to date it was possible. Well, at PCWorld they wanted to find out why and they have talked to AMD, who confirms that only two AMD RX Vega graphics configurations are allowed, at least in gaming.

The response received, in the form of email, talks about 'we have added bi-directional support for mGPU in games' and also, in the email received by PCWorld, they are further informed that 'the three-way and four-way configurations will continue to be compatible in computer and professional applications'. This move from AMD is not new, since NVIDIA with Pascal graphics, I already limit the number of mountable graphics cards for gaming to two, although at the insistence of users and the media, NVIDIA backed out and ended up supporting a 4-way SLI for gaming.

There is a trade-off to all of this and that is for CrossFire and SLI compatibility on mGPU setups, DX11 titles run flawlessly. Under DX12, in Windows 10, we need to explicitly set mGPU support in games and not trust profiles. There is some time left for mGPUs with three and four graphics for DX12 games, of which there are not many in the market, that emulate the DX12, so it will take time to see an official support for gaming under this graphics API. What's more, AMD is now scrapping outdated CrossFire technology in favor of the more powerful and efficient mGPU.