For sapphire: 1060-1080 Clock and 1600Mhz RAM
For Powercolor: 1050 Clock and 1500 Mhz RAM
ultracoinminer (pool info) --scrypt-jane --sj-nfmin 4 --sj-nfmax 30 --sj-time 1388361600 --failover-only --thread-concurrency 62720 --intensity 18 --lookup-gap 3 --gpu-powertune 20 --worksize 256 --gpu-dyninterval 5 --no-submit-stale -g 1 --scan-time 1 --expiry 10 --queue 0
Proud to be running -g 1 still

edit: not sure of catalyst / adl / sdk versions; but they're probably 10 months old.
Those are good settings for that card - without 3GB onboard, you'd have to make even more compromises on lookup-gap.

You might squeak out 5-10kh/sec more if you utilized a miner with xintensity

-g any higher than 1 makes no difference at these N levels on cards with 1024 shaders or more... even on the low end cards, they're able to max out at g=1
*edit* saw your additional posts... increasing TC only increases the scrypt buffer size, which you do not need to do beyond where you were at.