I saw this in the Anandtech review of the HD7970 V2:
http://www.anandtech.com/show/6025/r...p-to-gtx-680/3
Hopefully,similar performance improvements will be seen for HD7950 and HD7970 users.
Edit!!
Here is another comparison:
http://lab501.ro/placi-video/amd-rad...tion-review/22