For dual mining I get quite some ETH hashrate drop for little DCR, so for now dual mining on my gtx 1070 is a no go.
It depends on GPU, settings, selected coin, it's price and net diff. For example, for SIA on stock 1070 ccminer shows 1400MH/s. In dual mode in v9.7 I get 650MH/s SIA (so 45% of pure SIA speed) with only 2% ETH lost (about 25.8MH/s instead of 26.4MH/s).
DCR speed is not so good, agreed.
ETH: GPU0 28.884 Mh/s, GPU1 30.478 Mh/s, GPU2 30.198 Mh/s, GPU3 30.139 Mh/s
SC - Total Speed: 2992.474 Mh/s, Total Shares: 843, Rejected: 1
SC: GPU0 722.094 Mh/s, GPU1 761.959 Mh/s, GPU2 754.947 Mh/s, GPU3 753.474 Mh/s
gtx 1070 etc + sia
I would love to learn you setting mate. Currently 3 Asus Dual GTX1070 @ 8708MHz mem clock 80%TDP. I'm getting poor result on Sia. average 30.4mh/s for eth 350mh/s for sia per card which is not even half of yours. DCRI 35
-dcri 75 is giving me 22Mh/S for ETH instead of 30 with default value.
I really have no idea how did you manage to get both SIA and ETH performing like this