Do as above, and delete all your bin files (created when you launch your miner will have a long file name)

remove the TC from your settings And also remove shaders. start your miner, and see what number throws up after tc in the file name.

thats a good place to start for thread concurrency.

i got 3x 7950 running 715h/s @ about 75-81degrees C pulling 900w

thread concurrency is in the 20,000's intensity 13

[edit]

sorry am running 7970

tc 16384, mem 1500, i 13