[moved to hardware forum]
GTX 680. The 690 is a dual GPU card, which can only be used for 50%, since the second GPU is not supported, so the 690 is a waste of money.
The 670GTX 4GB card is the best performance for the price choice. The overall best card is the 680GTX 4GB card. One of those 2 would be your best choices.
This is not certified - would you recommend it?
Which is the best certified card?
The above gentlemen are correct, and there is absolutely no need for a "certified" card they both work fine you may have to add the proper name of the card to the Adobe "cuda_supported_cards.txt file". Take a look at our Premiere Pro BenchMark PPBM5 and see many non-certified nVidia cards on the list
Thank you very much - this was VERY helpful and illuminative!