You could also do it with one EVGA 1600W PSU and the price is about the same or cheaper than a EVGA 1200W and a EVGA 750W. The 1600W has all the connectors that you need. With good settings I can get the wattage down to 137W per GPU for the 1070's which equals 1096W. Then all the components minus the fans for me is 136W. I add about 10W or so for 5 120mm fans installed in a rack mountable case which brings my grand total to 1242W which is under the 80% rule for the 1600W power supply. This is a fairly precise estimation but I would always double check it at the wall when you build it. You can get an EVGA 1600W for about 390 dollars or so and the 1200W and 750W combined would end up costing about 410 dollars. IMHO the best choice here is the 1600W PSU. The prices are constantly changing though.
What kind of raisers i need for this setup, and i can get the Gainward Gainward GeForce GTX 1070 8GB GDDR5..
Think its also the best graphic card of the 1070 serie. but i dont know if i can overclock it to mh/s 32
And the Fan is enof? of do i need watercooling system