I am a bit confused.. the fan model is a reference one i think.. some people r telling me the 7850 OC could match the performance of the 7950 stock.. What to do? I play on 1080p
Neither. The only reason to buy a last gen card most of the time is to add a 2nd card for crossfire/sli, otherwise they aren't usually a very good deal.
The 7870 is 25% faster than the 7850 and the 7950 is 35% faster than the 7850. You'd be extremely lucky to OC it to 7870 levels.