It took me a while to figure out the setting for my 6950s, but after i got the hang of cgminer and the proper thread concurrency, i was able to run them at intensity of 19/20 putting out hash rates of 440-450 per card. i did also overclock them from 800 to 900. they've been running well for almost 2 months now. and considering that powercolor isnt exactly the best brand, im pretty happy with them so far. once in a great while one of the cards does go dead in cgminer, but i just restart the program and everything is fine once again. once i make enough profit i want to invest in another 2 rigs with 3 or 4 r9 280xs/ rig. im hoping batcoin will get this done for me. time will tell.