In early May, it was rumoured that Nvidia's upcoming GeForce GTX 660 mid-range card would use the GK104 chip, having part of the chip disabled to decrease the performance. The GeForce GTX 660 would have only 1152 shader units and possibly 24 ROPs, combined with a 192-bit interface.
According to SweClockers, Nvidia plans to launch the GTX 660 card in either July or August. The website reports that the GK106 will indeed be used on the card, which they claim is to feature just 768 shader units. The 2 GB of GDDR5 memory uses either a 192 or 256-bit memory interface. It's likely that a Ti version of the card will also be launched, in addition to a GTX 650 budget card. The upcoming GTX 660 is to be priced around 300 USD.

Image source: VideoCardz