It all depends on the factor that he gets an old die based card otherwise the 6950 will remain a 6950 and he will gain nothing
LOL all the currently available HD 6950 2GB models in the market(india) are the reference PCB ones only and unlock 100% to 6970 ! There is nothing as luck in this ....only thing might be it might no do core clocks as high as a binned 6970 but 1536 shaders @ 800Mhz core/1250 Mhz mem is 100% with the 6950 2GB Reference cards.
And ya I am sure OP would like to be a bit future proof and not like those people who got the 9800GT 512 MB models 2 years of so back are running into frame buffer issues ! 1GB cards were then told to be useless over 512MB. I for one will prefer either a GTX 560 2GB model (palit alreday relesed one) or a HD 6950 2GB Reference . When someone is spending 15000 it ought to run all the games in next 1~1.5 yrs @ 1080p w/o running into FB issues
The GTX 560Ti 1GB is a good value at max 13~13.5k ...anything over that better to get the reference HD 6950 2GB @17k. At the current 15k-16k for the current lot of GTX 560s....its a huge no no !
And ya just for the records I am on a HD 6950 2GB Sapphire Refernce PCB which is unlocked to 6970 and runs at 6970 speeds (both core & mem) with ease. With some voltage 950Mhz core/1500 Mhz memory is dead stable as well....leave alone GTX 560 at those clocks it gives the GTX 580 a run for its money too
Also in some of the review sites allmost all of them were using Catalyst 10.12a Hotfix and not the latest Catalyst 11.1a ! Baring few all had left Powercontrol at default....it has huge implications on fps when HD 6950 @ 6970 unlocked and OCed
But if someone has a CF mobo...the 6850 CF looks hell good at arnd 18.5k or so
http://www.anandtech.com/bench/Product/305?vs=302
It runs almost 10-20% faster than a GTX 580 and almost as fast as HD 5970 costing 38~40k :O
http://www.anandtech.com/bench/Product/297?vs=302