The second core of my 7990 is not being used while playing FFXIV DX11 since installed 16.1. The second core activates for every other crossfire supported game and even for DX9 of FFXIV. Crossfire used to run fine with FFXIV in 15.12 but now it's gone. Any help?
It sounds like it could be a bug, but please try pressing Alt + Tab whilst the game is running. This should switch between Windowed mode and Fullscreen mode and it may activate CrossFire. If it does not, please report the issue here and roll back to Crimson 15.12.