18 is not bad result with current DAG size
Ethereum is very memory intensive.
Run stock, and ether only mining, then with Afterburner try increasing mem speed through
1250 - > 1375 -> 1500 and check speed
Stock, or moving memory/CPU clock speed does not change anything.
18.1 dual mining
17.9 solo eth mining
Changed to 4.0 no difference.
Thanks