At 0.4W/GH board-level you could be seeing closer to 15GH per chip and 110W per board. 8.2GH per chip you should expect about 0.3W/GH and under 50W per board. That's at what I hope to be a low estimate for regulator efficiency. If you ran them up to 15GH per chip you'd see 272GH per board, so almost 2.2TH and 900W from an 8-board waterblocked system. Which if those waterblocks can handle 4x S5 boards (~1200W) they can surely handle a 900W load.
Top end for the chips would be about the same as an S5, estimated 22GH (400MHz) at hopefully 10.5W board-level per chip. The overall system efficiency for top clock would actually be between 5% and 10% worse than an S5 (hopefully closer to 5%), but the overall benefit of having adjustable voltage gives you access to a lot lower efficiency ranges than the S5 is capable of doing - same as with undervolting an S1 to get from 2W/GH down to 0.8-1W/GH board-level - which greatly increases the service life of the machine without requiring hardware modification to reach the low end.
In my estimate I was "worst casing" it.
The S3/S5 bolt pattern compatibility is addressed here:
https://bitcointalksearch.org/topic/bitmains-refused-from-s9-warranty-buy-at-your-own-risk-914354and here
https://bitcointalk.org/index.php?topic=947254.msg11464031;topicseen#msg11464031In our experience, the heat absorption capability of these waterblocks is dependent on flow rate and coolant composition. We like and use a 50/50 mix of water and automotive green antifreeze (Walmart brand). But pure (de-ionized) water has better thermal capabilities. I might add that all the tubing we use is of the oxygen barrier type (metal, PEX, etc. . .).
We never string more than 2 waterblocks in series, as the coolant temps can become excessive feed to the last waterblock in the chain. This is due to the flow capability of a 3/8" pipe at less than 5psi differential pressure.
We've found that each pair of waterblocks need just under 2 gpm (~450L/hr) flow.
All things being the same, 4 3/8" pipes = 1 3/4" pipe and 4 3/4" pipes = 1 1.5" pipe, from a flow rate standpoint.
So 1 1.5" pipe, manifolded down to 3/8", will service 16 pairs of waterblocks (64 boards).
So on the circulating pumps/circulators we run 1.5" in and out pump manifolds.
And use the Taco 0010 w/IFC (
http://www.supplyhouse.com/Taco-0010-F3-1IFC-0010-Cast-Iron-Circulator-with-Integral-Flow-Check-1-8-HP-3778000-p) w/ 1.5" manifolds (
http://www.supplyhouse.com/Taco-110-254F-1-1-2-Taco-Iron-Freedom-Flange-Pair-1976000-p).
Another thing that bears mentioning is that these "pumps" are really not pumps in the purest sense of the definition. They're circulators, as they are designed not to build pressure and as such have a reduced capability to "pump" into a head. So the maximum distance between the high point and the low points in the system is restricted.
Didn't mean to hijack the thread so I'll shut the F* up.