I am getting 14 Mh/s from my tri-x r9 290 on 1080 gpu clock but for better stability fall back to its reference clock. getting 11+ now. In r9 270 Non X I am getting 6+ Mh/s on 1050 gpu clock. But most exciting thing is I am doing solo mining and my 2 rig point on one wallet and speed of 2 rig combined is 52 Mh/s(I swear I will make it 5 Mh/s more. Just tired). In this speed in pool mining I should get 1600 coin and I already found 3 block in first 7 Hour. Been lucky. Hope luck will remain but also fun on setup(No specific tutorial for GroestlCoin. I set it up based on litecoin. Fun is there). Happy mining.