Its rumoured that AMD is working on a GPU to have a head-to-head competition with Nvidia GTX 780Ti and even GTX Titan Black.
It is said that AMD would be implementing newer technologies such as high-bandwidth memory which involves stacking of multiple DRAM dies. This process will help to save space on PCB and even reduce power consumption by the DRAM. These will be 8Gbit 4Hi which will work via 128-bit bus. There would be four layers of DRAM module, each with 1GB memory with the bandwidth up to 512 GB/s.
As of now, its assumed that AMD might name this card as Radeon R9 295X2, but that remains to be seen. In any case, AMD wants to concentrate on providing a good single core GPU offering. So it should be interesting to see how AMD’s unnamed card would perform. These would be based on AMD Volcanic Islands refresh.