Wouldn't be the first performance bench that puts it just a tad behind a 390X.Using scaling from 390X vs Fury X benchmarks, it'd put the RX 480 slightly below a 390X. Would hope it beats it come release and driver updates and in the hands of someone who wouldn't bork his card on a live stream.
I dont think drivers are going to magically make it significantly more powerful in just a week or so, but I do hope that in general gaming performance, it can match or beat a 390X in most cases.