It is somewhat ironic that they finished the design on what seems to be the somewhat less stable model (B8) according to first reviews.
It probably should work better at 650.
I have a S7 with a bad Hashboard. I am sending the bad Hashboard back to Bitmain. Has anyone run the S7 with only 2 Hashboards? If so, What did you plug the opening in the place of the missing hashboard to make the air go through the 2 running Hashboards?
I have 2 units running 2 hashboards as the 3rd unit failed in both.
I made sure to run the 2 hashboards spaced left and right and put a strip of duct tape over the middle port on the s7.
Seemed to do the trick with keeping airflow through the other 2 hashboards. One board does seem to run 2-3 degrees c higher than if all 3 hashboards were in though..
Out of all my orders
19 batch 1 - all hashing good (2 units running 4780 ish others around 4850)
20 batch 5 - 2 hashboards failed and have been sent back to Bitmain for replacement. - failure occurred after 2-3 days of use.
(all remaining units hashing around 4850)
10 batch 8 - just arrived. Have only 1 running - 20 minutes now at 4580. Waiting for more PSU's to arrive for other 9 units.