It looks like AMD's next-gen GPU will be arriving in Q2 2016, which is the rough timeframe that we expected from all the rumors over the last few months.
AMD's new part will be made on the 14nm process by Samsung and GlobalFoundries, with it reaching mass production at the end of Q2 2016 - or in June. This is perfect timing for Computex 2016, as we saw the rumors - and the TweakTown exclusive during Computex 2015 that the new card would be called the Radeon R9 Fury X, and not the Radeon R9 490X that the world thought.
The new GPU will feature HBM2, which will not only increase the amount of VRAM that the new GPU will have - up from the 4GB of HBM1 found on the current Fiji cards like the Fury X and R9 Nano - but it will also see an increase in memory bandwidth. HBM1 allows for 512GB/sec, while HBM2 drives the memory bandwidth numbers through the roof to over 1TB/sec. We should expect to see cards from AMD featuring up to 18 billion transistors, and up to 16GB and even 32GB on the professional cards in 2016.