The 7970 is about $60 more than the 7950s. Is the performance difference worth it? I have a 2560x1440 monitor. I would also overclock it. I may eventually get another card if I get any more monitors but it wouldn't be soon.
Well imo, I would pay the extra money just knowing that I would have the best AMD card because then you wouldnt need to buy another card for a long time lol. But I think I heard the 7950 was a downscaled 7970. So you could technically get the 7950 and overclock to a 7970 assuming that what I said was correct.
I'd definitely go with the 7970. If you're really tight on money and you can get the 7950 but can't get the 7970 by any means, that's still OK, because overclocking it would potentially wield the same results as a 7970, but if you do the same OC'ing with the 7970, imagine what would happen then... both cards are great though.