Zooshooter :
It's funny you post this question here when this article was right up at the top of the home page: http://www.tomshardware.com/reviews/gaming-graphics-card-review,3107.html
The article is worthless as it only takes into account regular retail prices. The Sapphire 7970 was $300 after rebate for the last 2 weeks(expired yesterday) and it is on par with the $400 GTX 770 once overclocked.
Powercolor 7970 is still available for $310 but doesn't overclock as well as the Sapphire since it lacks VRM cooling.