NVIDIA Kepler GK104 Cards in Production, Hitting Retail in April 2012
NVIDIA's partners are starting the production of the 28nm Kepler based GK104 cards, Fudzilla reports. Nvidia has briefed their partners who have also acquired the reference design of the boards, Also most of the parts available at launch would look similar to each other due to similar cooling but expect non-reference cards from AIB's later on.
If everything goes well, The cards would hit retail in the first two weeks of April (Reports also suggest a Gk104 part in March 2012). Xbitlabs also reported a while back that Nvidia was facing 28nm yeild issues however CEO Jensen later addressed that its nothing like the transition to 40nm with the GeForce 400 Series.
The cards you can expect at launch can be the GeForce GTX680 or the GeForce GTX670Ti, Both look like solid performers as early rumors suggest with performance on par with HD7970 (AMD's Flagship 28nm GPU) and better than a GeForce GTX580. The entry level GK107 is also expected to be released around April 2012, The high end GK110/100 would launch in Q3/Q4 2012 on which the next flagship part would be based.
On the other hand, AMD is expected to launch the last GCN based GPU's - HD7800 Series (Pitcairn XT/Pro) in March. More on those here.