AMD Bids Farewell To CrossFire After 12 Years, Retiring Brand In Favor Of mGPU
AMD revealed today that it no longer refers to multi-GPU support by its long-standing Radeon brand known as CrossFire. This revelation came via PCWorld's Brad Chacos, who was curious as to why Crossfire wasn't mentioned in the company's latest Radeon Software 17.9.2 drivers. He proceeded to email AMD to inquire about this apparent omission.
To his surprise AMD's answer was that it's transitioning away from the CrossFire brand, referring to it as a DirectX 11 era technology. “CrossFire isn’t mentioned because it technically refers to DX11 applications,” an AMD PR person told PCWorld. “In DirectX 12, we reference multi-GPU as applications must support mGPU, whereas AMD has to create the profiles for DX11. We’ve accordingly moved away from using the CrossFire tag for multi-GPU gaming.”
AMD further elaborated by saying that this is simply a branding decision not a technical one. The company is by no means ending multi-GPU support for its graphics cards, in fact its latest drivers enable multi-GPU support for its recently released Radeon RX Vega graphics cards with promises of 80%+ performance scaling.
Gone are the days of old when graphics card vendors had to hand-craft and optimize CrossFire & SLI profiles for multi-GPU to work at all in games. DirectX 12, unlike all of its predecessors, delegates this responsibility entirely to the game developer via a feature called Explicit Multi-Adapter. The API enables low-level access to the hardware, allowing developers to access each GPU directly and independently.
One GPU could render one portion of the frame while the second could render another portion of the same frame for example. This is called Split Frame Rendering, SFR for short. This technique negates the limitations inherent in the traditional alternate frame rendering – AFR – technique used today in DX11 and older games, which involves mirroring the memory pools and introduces the need for frame pacing.
This brings is to the concepts of CrossFire and SLI, which were introduced over a decade ago. As you can clearly tell the new new DirectX 12 multi-GPU capabilities have very little to do with SLI and CrossFire, which are essentially proprietary algorithms developed by each vendor to enable alternate frame rendering via the driver layer. Hence calling DirectX 12 multi-GPU support SLI or CrossFire is simply not accurate.
DX12 in and of itself does not rely on the proprietary SLI and CrossFire technologies that NVIDIA and AMD have developed. DX12 multi-GPU support stands on its own two feet. All that's required of the vendor is to make sure that their hardware and software is compliant with the multi-GPU features built into DirectX 12. This is why AMD isn't calling multi-GPU support in its latest driver release CrossFire, because it simply is not. Not anymore.