This is a similar question to one that's been asked many times before, pertaining to earlier versions of Premiere.
With CS6, some cards not on the supported list could be added via a "hack". Can a similar modification be made for Premiere Pro CC ? And if so, how and where ?
Something related to Premiere- I also wonder if Speedgrade can support my GTX 670.
Yes you can edit the same file with CC to add support for a card. Speedgrade supports any card that has Open GL version 2 or higher and 1GB of Vram.
After some searching around, I found this page from Adobe > http://blogs.adobe.com/premierepro/2013/06/adobe-premiere-pro-cc-and-gpu-support.html
According to that page, selecting non certified cards now only requires a simple change in the project settings.
Yes but last I checked there is a bug where the hardware MPE wont initialize on export/media encoder if the card is not on the supported list.