Nvidia may deny the imminent release of their next gen gaming GPUs all they want, however, more evidence for a Q3 2018 GTX 11xx release has recently been unveiled by Power Logic's CEO. The largest GPU air cooling provider on the market is expecting a considerable increase in cooler shipments in the second half of 2018, essentially confirming Nvidia's and AMD's next gen GPU arrival.
https://www.notebookcheck.net/New-Nvidia-GTX-11xx-series-essentially-confirmed-to-launch-in-Q3-2018-according-to-GPU-cooler-maker-Power-Logic.309656.0.html