So, guys, I 'm updating with my experience in these days:
My rig is composed by:
3x gtx 1060 3 gb
1x gtx 1070 8 gb
+-----------------------------------------------------------------------------+
| NVIDIA-SMI 390.48 Driver Version: 390.48 |
|-------------------------------+----------------------+----------------------+
| GPU Name Persistence-M| Bus-Id Disp.A | Volatile Uncorr. ECC |
| Fan Temp Perf Pwr:Usage/Cap| Memory-Usage | GPU-Util Compute M. |
|===============================+======================+======================|
| 0 GeForce GTX 106... On | 00000000:01:00.0 On | N/A |
| 50% 58C P2 60W / 140W | 370MiB / 3019MiB | 80% Default |
+-------------------------------+----------------------+----------------------+
| 1 GeForce GTX 1070 On | 00000000:02:00.0 Off | N/A |
| 41% 62C P2 67W / 140W | 445MiB / 8119MiB | 83% Default |
+-------------------------------+----------------------+----------------------+
| 2 GeForce GTX 106... On | 00000000:04:00.0 Off | N/A |
| 62% 54C P2 51W / 140W | 355MiB / 3019MiB | 80% Default |
+-------------------------------+----------------------+----------------------+
| 3 GeForce GTX 106... On | 00000000:05:00.0 Off | N/A |
| 62% 52C P2 53W / 140W | 355MiB / 3019MiB | 85% Default |
+-------------------------------+----------------------+----------------------+
Initially, i was getting around 400-500 h/s total (1 miner instance), after that, I decided to run 3 instances and now I'm getting from 800 to 950 h/s with a total consumption of 220 w.
I had also to create a swap file due to miner taking lot ram.
On the pool i'm getting an average hashrate of 766 h/s