Hi NeM3Si,
it seems that you have recessed and complex emissive geometry inside specular/transparent material, that is the worst condition for Path Tracing.
If you don't
semplify the complexity, you need a very high Max Sampling, possibly with Adaptive sampling, to clean up the reflections:
viewtopic.php?f=24&t=60014Or switch to PMC and wait a bit more.
ciao beppe