After CES2018, AMD told people in a breakout session, that they cancelled the implicit driver path for Primitive Shaders, they are now offering only explicit control to developers who wishes to implement it. So Primitive Shaders will only be ever implemented if a developer properly codes for it. The driver portion has been cancelled. This comes directly from Marc Sauter (y33H@), editor at the german IT site Golem.de. Source: https://www.forum-3dcenter.org/vbulletin/showthread.php?p=11610696#post11610696 Source 2: https://www.forum-3dcenter.org/vbulletin/showthread.php?p=11611522#post11611522 Source came from: https://www.reddit.com/r/Amd/comments/7sedpq/amd_cancels_the_driver_path_for_primitive_shaders/ If this true Lawsuit in coming from those who own RX Vega GPU.