The 380x did 25mhs until the latest dag, now it's doing ~21mh so with the 14nm chips in the 480 should offer a jump in performance and efficiency, especially for claymore's dualminer.
whaaaat?! do you got some real ethereum miner pics?
PS 380x of mine pushes 21.45mh/s @1500MHz gddr5 (elpida)
now i can do 23.5mh/s @900/1625 (elpida-mod bios)
The 380 will never slow down for the DAG change, those only affected the Pitcairn and Tahiti based cards, not Tonga.