Quote
I wouldn't be so sure. I think they can squeeze 2 TH/s out of 1100-1200W.
2000G * 0.7W/GH = 1400W MINIMUM...OK... 
The assumption is that the S4 works with underclocked/undervolted ASICS to reach a better W/GH ratio, I would assume somewhere between 0.55 and 0.65 W/GH, so one 1300/1400W power supply could indeed do. But of course we'll not know for sure till @BITMAIN reveals the exact specs.
Evga 1500w Platinum
and, btw...
5units of S3+ = 355w x 5 = 1,775W
i assume S4 will be around 1500w - 1700w
they wont waste chips like that..
they better selling chips like avalon do than planting so much undervolted chips
and sell it so damn cheap
they're not doing charity here buddy