AMD demonstrated the world's first 7nm GPU architecture at Computex 2018. The Radeon Instinct series of accelerators are made for High Performance Compute (HPC) applications and feature 32 GB HBM2 memory on a 4096-bit bus. The 7nm Vega GPUs are currently being sampled with targeted availability in 2H 2018.
https://www.notebookcheck.net/AMD-demonstrates-Radeon-Instinct-7nm-Vega-GPU-platform-with-32-GB-HBM2-memory.307988.0.html