I think overclocking is going to be extremely limited, with four TPS53355 per board, or one for 16 chips. On the S1, it's one for 8 chips.
Thats the detail I've been waiting for
*really hoping for a PCB photo still*The S1 could consume around 45W per group of 8 chips overclocked (overclocking pushed the regulator right to its limits, but the real limiting factor was the voltage being set to 1.1V - some people have apparently pencil-modded the S1 to almost 215GH/~470W, or about 60w/8 chips)
45W/1.1V=40.9A on a 30A-rated component. (bitfury h-boards faced very similar amperage limits when overvolted around 0.95V)
Its likely these chips run at around 0.8V and 1000W/640chips is about 25W per cluster of 16. That leaves a LOT of headroom on the regulators, but some of this is lost to the difference in voltage (more amperage). 25W/0.8V= 31.25A stock.
Presumably these should be able to overclock without any issues from the regulator. I imagine all other components are beefy enough also. I imagine you will hit hardware errors at 15-20% overclock as with the S1. These may even be capable of up to 1.5TH is voltage was increased to ~0.9V