I just bought a new iMac with Radeon Pro 580X GPU which supports OpenCL but neither Blender 2.8 nor 2.79 can, for some reason, utilise it with Cycles render engine. The program just says that "No compatible GPU found". I have read that others have managed to use Cycles with GPUs with their Macs so I have no clue what's wrong here.
Can anyone try to help me out here?