The chaps over at HotHardware is reporting on the recent GPU PhysX cheating allegations leveled against NVIDIA. They talk to several folks at NVIDIA, Epic Games and Futuremark in an attempt to shed a little more light on the situation. What do you guys think of this whole deal?

HotHardware: We recently became aware of the accusation being thrown about in the industry regarding NVIDIA allegedly "cheating" in Futuremark's 3DMark Vantage benchmark via an offload of PhysX-based physics calculations that were previously sent to the CPU that, with the latest 177.39 driver release, now are sent to GPU for PhysX processing. Could you explain exactly what is being done currently in your new set of PhysX-enabled drivers with respect to 3DMark Vantage, the software libraries that may or may not be replaced, and the impact it has on the benchmark?

NVIDIA, Taylor: During the benchmark install, a runtime library is updated to allow the test to run on the GPU and then during the test, it addresses the benchmark DLLs to the GPU instead of the PPU or CPU. Nothing within the benchmark is changed at all. No software libraries or even a line of code changes in the benchmark whatsoever. The only thing that changes is that installer, nothing else. It has been said that the tests results look different on the screen when running with PhysX enabled on the GPU. And of course this is true, just as the screen results look different when you test on a dual-core CPU versus a quad-core. This isn't a graphics test; it's a physics test. 3DMark Vantage specifically scales more complexity into a scene to take advantage of additional physics compute resources, which of course is why it looks so different/better on a test run with PhysX processing on our GPUs. This is by design in the benchmark and if the folks accusing us took the time to run it, they would know that.

NVIDIA are just trying to brand it as a 'pure' physics test, and that it should not matter whether it is CPU or GPU handled.