DaVinci Resolve could not find any Cuda capable GPUs (15b)

Had been using Resolve 14 on my dual Xeon E5-2667 with nVidia Titan X for about a year and just tested it on an older Core2 Quad machine with no problems, so I took the plunge and upgraded Resolve on my main machine which has been running v14 fine.
Old machine: Core2Quad, 8GB RAM, GTX680 -- DaVinci 15 beta runs.
New machine: dual Xeon E5-2667, 128GB RAM, Titan X -- DaVinci can't find a GPU.
The new beta version won't start. It complains that it can't find my GPU. Have they dropped support for the Titan X in this version?
Old machine: Core2Quad, 8GB RAM, GTX680 -- DaVinci 15 beta runs.
New machine: dual Xeon E5-2667, 128GB RAM, Titan X -- DaVinci can't find a GPU.
The new beta version won't start. It complains that it can't find my GPU. Have they dropped support for the Titan X in this version?