only AE's ray tracing isn't functional. people have been using the 900 series cards just fine with premiere and other apps for a while now.
The GPU acceleration in Premiere, AME, and Speed Grade work fine with the 900 series cards. Ray Tracer is a completely different GPU acceleration from those and was in AE CS6. After that Adobe phased out support for Ray Tracer in favor of the link to C4D. Most of the time Ray Tracer was not even utilized or slowed the process down so your better looking at C4D anyway. There is Octane for C4D which is the GPU acceleration render engine. I would suggest looking at that if you need C4D.