Simply their new software/driver suite. The Crimson moniker is done and they've moved on. Adrenalin adds monitoring and OSD functionality, better Relive system usage, Chill enhancements and more. There is also performance upticks for the RX480 series and above.

That said, I am having issues with graphical corruption in Frostbite based games and had to roll back to 17.11.4.