I maintain a hobbyist benchmarking channel, in which I benchmark everything I got.
I have uploaded many 7950 videos during the past year, among others.
https://www.youtube.com/user/toutagamon/search?query=7950+benchmark
All vids that are less than one year old, are digitally recorded with an external recorded as well.
See if you see anything you may be interested in. I use 1.1Ghz for the video card (skip the crossfire ones so you don't get confused), so it would be pretty close to your 7970. Actually maybe a bit faster, but you still would get better performance if you overclocked.
It is not a top performer, especially when I compare it with my 970, but hey for its age, it's doing great. I believe it will be the new 5850 and even more so, due to it having 3GB of Vram.
Be warned for spicy wallpapers though, heheh.