The final specifications of NVIDIA’s Upcoming Kepler GK104 based GeForce GTX680 graphics card have been leaked at VR-Zone (Chinese). The site reports that Nvidia will launch a 28nm product based on the GK104 chip on 12th March and would be available globally on March 23rd.
The specifications were acquired from a very reliable source which suggests that the GK104 would hold a total of 1536 Stream Processors, Core clock would be set at 705Mhz and Processor clock at 1411Mhz. Memory would consist of 2GB GDDR5 (256-bit) buffer clocked at 3004MHz (6.0Ghz Effective Dual Data Rate).
Leaked PCB shots of the card which were reported last week (Detailed here) suggest that the card would either feature 2 x Six Pin or 1x 8 Pin + 1x 6 Pin PCIe connector and a die size of 320mm2 which is 45mm square smaller than the Tahiti XT chip. A 5-phase NVVDC configuration powers the GPU, The green pcb suggests that the card is in engineering phase, Final product would feature a black PCB.