Lack of shaders doesn't matter too much, since they aren't fully utilized. As far as I am concerned, this is why we can OC these cards so well...they are barely used properly.Yeah I know the CPU is the big difference in overall score - the thing that surprised me was the graphics subscore, which is more or less identical on your 7950 and my 7970.
Plug in a bunch of meters and check power consumption, and you'll see what I mean, I think. The same is true for ANYTHING on 7-series. 7970's raised cost is stupid, since it doesn't justify that cost with performance over the 7950, at all. 33% more money, 2% performance increase.
AMD depends on the clock differences to make the real difference between these cards. Overclockers know better. I started with 7950's for EXACTLY this reason.
Keep in mind, my full rig with 3960x @ stock, pulls 500 W. with 3770k, it drops to 400 W. and easy 100W is the system including CPU, mem, drives, board ,etc, leaves 300W for the VGAs, or just 150W each. 7970 increases that a wee bit, about 35W at most with my cards. 7950 is spec'd to 225W, my benched 7950 card pulls 326W @ 1300 MHz. That's a huge increase.
I also feel that the bad memory management here on 7-series really hold the 7970 back from making proper use of it's shaders. I've mentioned before that the problems with this gen are obvious, now more info makes this easier to understand, I think. The flicker and stutter problems, poor shader utilization, low power draw, etc, etc...it's all down to the memory management.