I have a GeForce GTX 285 that was working fine with Premiere CC. However Premiere CC 2014 failed to recognize my card. After not finding a definitive fix here is what has worked for me.
I located the file: C:\Program Files\Adobe\Adobe Premiere Pro CC 2014\cuda_supported_cards.txt and noticed that the last line was not terminated. Possibly not a problem but I have found that to be a problem in other apps. So I not only added a carriage return after the last card name, but also copied and pasted my card name again as both the first and last lines of the file (probably overkill).
So far things are working.