Not sure why people compare clocks 7970 vs 680... Both different cores, and 7970 has 25% more cores. Its really a moot argument.. It really comes down to any of these three:
1. Raw stock performance / price
2. Maximum overclockable performance with stock cooler / price
3. Performance / watt
Then there are further breakdowns:
1. Performance / feature (resolution / AA / Tesselation / DX11)
2. Performance / Game (specific games you play)
3. Performance / SLI or Crossfire / multi screen setup scaling
It can go any way, but it really comes down to what you pay for the stock performance it comes to. To get a factory OC 7970 you generally pay more.. At that point it starts matching the 680 for $100 over the 680..
Thats fine for your average Michael, on Overclockers.com we are not your average user.
To try another way to explain what i'm getting at i will use a system of scenarios.
A:
I'm buying a new GPU today in this range and have never heard the word overclocking.
I will buy the GTX 680.
Why: cheaper / better performance / better drivers.
B:
I am an overclocker.
Clock for clock they perform similar right up to there highest clocks on stock cooling.
I will buy the GTX 680.
Why: cheaper / better drivers.
C:
Clock for clock they perform similar right up to there highest clocks on stock cooling, the 7970 comes down to the same price.
I will buy the GTX 680.
Why: better drivers
D: The 7970 out performs the 680 overclocked, the 7970 still costs more.
could go either way, depends on how much the 7970 out performs.
D1:
As above but the 7970 costs the same.
I will buy the 7970.
Why: better performance for my money
E: AMD release a Ghz version and price it the same as the GTX 680, it performs the same.
I will buy the GTX 680.
Why: better drivers.
E1
The 7970 Ghz version out performs the GTX 680.
I will buy the 7970 Ghz.
I would not base my decition on one reviewer, i would look at all of them to get the full picture.
especially if some reviews are incomplete.
My decision would be based on a wide range of games, the full power consumption tests, and the full range of resolutions on all games tested and the full range of overclocking, again on all those games.