NVIDIA held their GTC keynote yesterday and while most of it was geared towards developers and researchers there was an interesting announcement. NVIDIA will be allowing rudimentary DXR ray tracing support to older hardware that does not have RT cores. Next months driver update will add those support for 10-series Pascal graphics cards (GTX 1060 6GB and higher), as well as the newer 16-series cards (GTX 1660 Ti / GTX 1660). NVIDIA is letting people know not to expect RTX support like the RTX series though (think lower number of ray traces, and possibly no secondary/tertiary effects) and the DXR will only be supported in Unity and Unreal engine games for now.
NVIDIA is saying that DXR mode will not run the same on Pascal GPUs as compared to the new Turing GTX cards, given how Pascal cards can only run ray tracing calculations in FP32 mode, which is slower than what the GTX cards can do via a combination of FP32 and INT32 calculations. Both will be slower and less capable of hardware with RT cores, which again is to be expected. NVIDIA showed this in a single frame of Metro Exodus.
The MMO title Dragon Hound will be one of the first game titles to have DXR support for GTX cards. This will be followed by titles that already have RTX support like Battlefield V and Shadow of the Tomb Raider and synthetic tests like 3DMark’s Port Royal.
NVIDIA has mentioned that they are working with partners across the board to get DXR in game engines. This will greatly help to get DXR going.