AMD went on the record at a Computex press conference and said it will launch Vega at the Siggraph conference that starts on the July 30.
We have been hearing that Vega has been delayed for quite some time, but we cannot yet understand the reason for the delay. The card that we saw back in December and February appeared fine but apparently, AMD is struggling to bring this piece of technology to the market.
High Bandwidth Memory 2 (HBM2) is not in short supply, so this can be ruled out. However, it remains to be seen if there is a manufacturing problem. It is hard to imagine that this could be driver-related, as the driver team has mostly improved the quality of drivers for the Polaris series tremendously.
In the past, we've heard that Q2 2017 was a solid release window, but now that we have hard data, this window still seems shut. As it stands, Nvidia is working hard on its next generation of 12nm FinFET Volta cards that will put even more pressure on Vega.
Vega performance should be somewhere between Geforce 1080 and the Ti, so keep in mind that the next generation of Nvidia products using Volta graphics is going to end up faster than the Titan and Ti. For AMD, graphics will be hard to win this time round.