First of all, you were incorrect.... It's not 1400, and also not 1300. It is, as i have suggested, 780, as could be easily calculated from the product description
here. Each chip is 400 GH/s, there are 3 chips for 1200 GH/s total. At advertised .65W/GH, that totals to 780W. Any other number you arrive at directly contradicts the company claims.
Try to learn something for once. The efficiency of the CHIP isn't the entire power requirement of the entire system.
Each chip uses ~0.65 J/GH. @ 400 GH/s that is 260W @ ~1VDC. However no chip runs at 12VDC and thus the 12VDC has the be converted to ~1VDC. High current DC to DC regulator is ~90% efficient so that is 288W @ 12VDC per board. The watercooling system requires power as well. How much? Not sure but lets guestimate. Each includes 2 fans likely high RPM so lets go with 12W ea and a pump say another 6W. So 30W per cooling loop so 318W for board & cooling. 954W per rig.
At nominal hashrate (400 GH/s) & 0.65 J/GH.
Per chip - 260W @ 1VDC
Per board - 288W @ 12VDC
Per board including cooling - 318W @ 12VDC
Entire System - 954W
However that is only at nominal 400 GH/s hashrate. Hashfast has indicated they believe the chips can be pushed harder. How hard? Well we won't know until they get final silicon but lets say with a small voltage increase 10% they can push the chips to 520 GH/s. In Silicon devices, power consumption increases by the square of the voltage increase. So 10% higher voltage = 21% higher power.
AS AN EXAMPLE ONLY 520 GH/s @ 0.78 J/GH
Per chip - 408W @ ~1VDC
Per board - 454W @ 12VDC
Per board including cooling - 484W @ 12VDC
Entire System - 1363W @ 12VDC
So designing around a 780W power supply would limit the potential of the device. HashFast has indicated there were no power supplies from vendors they liked which had a high efficiency power supply in the 1300W to 1400W range and that even if one was available the price tends to be higher than two smaller units. SeaSonic for example maxes out at 1250W and a 1250W unit is more than 2x 750W ones.
Yo are the only one suggesting designing around a 780W PS. Go back and read my post again, and try to learn something for once. I guestimated 900W, and pointed out that a 1000W power supply, available from Sea Sonic, would suffice for the stock specs. For extra credit, try to ell me where i went wrong.
If you're a modder & wish to overclock, go out and buy (again) a Sea Sonic 1250, or any of the quality 1600W PS. Elementary. You get even MOAR watts.
As an example, running the 3 chips @767GH/s would require 6000W & a liquid nitrogen cooling system. I'm surprised they have omitted the hardware allowing for *that* eventuality. Cutting corners, i suppose

Just stop. The make-believe math makes you look ridiculous --
there are no chips. The numbers you're quoting could be off by a factor of 10, if Hashfast's case design is any indicator

Edit: Case design -- the renderings, that is, is the only thing we have to judge Hashfast by.
No chips.
No boards.
No photos of *anything*.
Just some 3=D renders & a stolen Intel CPU pic.
