Dutch tech site Hardware.info claims the Radeon Fury X with 4GB HBM will not be a Titan X killer. In fact, the performance with current drivers is said to be a tad slower than that of the GeForce GTX 980 Ti. The Fiji XT GPU is allegedly clocked at over 1GHz and has a TDP of "under 300W".
Rumors are also circling the web that a version with 8GB HBM may follow in August.