Games that integrate Nvidia's Gameworks development tools are being deliberately restricted on AMD graphics cards, the latter has claimed.
Titles such as Watch Dogs, Assassin's Creed IV and Batman: Arkham Origins have all taken advantage of Gameworks and as a result, AMD's Robert Hallock told a Forbes contributor, performed disproportionately bad for owners of AMD GPUs.
Gameworks represents a clear and present threat to gamers by deliberately crippling performance on AMD products (40 per cent of the market) to widen the margin in favour of NVIDIA products,” Hallock said.
Participation in the Gameworks program often precludes the developer from accepting AMD suggestions that would improve performance directly in the game code – the most desirable form of optimization.
The code obfuscation makes it difficult to perform our own after-the-fact driver optimizations, as the characteristics of the game are hidden behind many layers of circuitous and non-obvious routines. This change coincides with NVIDIA's decision to remove all public Direct3D code samples from their site in favor of a ‘contact us for licensing' page. AMD does not engage in, support, or condone such activities.”
Note that AMD has a policy of open coding, meaning tech such as TressFX and FreeSYNC do not offer performance gains on AMD hardware.
However, the accusations were firmly refuted by Nvidia's director of engineering and developer technology Cem Cebenoyan.
I've heard that before from AMD and it's a little mysterious to me,” he said. We don't and we never have restricted anyone from getting access as part of our agreements. Not with Watch Dogs and not with any other titles.
Our agreements focus on interesting things we're going to do together to improve the experience for all PC gamers and of course for Nvidia customers. We don't have anything in there restricting anyone from accessing source code or binaries. Developers are free to give builds out to whoever they want. It's their product.
The way that it works is we provide separate levels of licensing. We offer game developers source licensing, and it varies whether or not game developers are interested in that. Now, like any other middleware on earth, if you grant someone a source license, you grant it to them. We don't preclude them from changing anything and making it run better on AMD.”