You have a broken miner.
Is it just me, or does it seems like the S7's are one of the most problematic Bitmain products ever ?
It only seems to you.
3 broken blades from 99 is not to much.
This situation arose for me from one PSU and two times.
I have using this setup.
1 x Corsair RM 850 with controller and 1 board
Corsair RM1000 with another 2 boards.
Corsair RM850 turned itself out and another 2 boards are powered for some hours.
If I restarted miner from PSU switches, came from miner hot air and the smell of burnt.
I put in there the other miner, with the same PSU-s, and after day was the same with 1 board with another miner.
Always the blade(s), which was powered with RM1000 and after that, when RM850 Switch off for some mysterious reason.
This RM850 works for me today with 3x Antminer S5 blades water cooled , so
perhaps it is not the fault of the PSU He bears the load about 850-885 W
However, the conclusion is, use only 1 PSU per miner.
I am running my S7 with the RM 1000 and RM 850. The only problem I have is I notice the 850 felt warm and did not see the fan running as both fans only turn on when needed so they are hard to know if the fans are working or not. I went ahead and placed a fan to blow air thru it and it's much cooler now. But they have been running the miner fine for going on a couple weeks+ now.
You probably have the 850 on one hash board and the 1000 on the other two.
The 850 will only be pulling 400watts so the fan won't spin.
The 1000 fan will spin because it is pulling 800 watts.
For me all three rm1000 fans spin because they are all pulling 800 watts.
I did have a problem where one of the rm1000 did not switch on even with the jumper.
Caused the miner to think that two blades were partially on but only hashed at 1.5th.
Sometimes the controller lies. I would think that with no power to two boards that only one set of chips would show up. Not the case. I put a spare rm1000 in place of it and it worked fine after that.
I had to rma the rm1000. They sent me a brand new one. They have 5 year warranty. Ax860 ax series has a seven year warranty.
I did get four bitmain 1600 watt psu's so they would fit in a smaller rack.
They have been running fine since I got them.
If you read some history the RM series PSU's were faulty. Or at least a huge batch of them. This is why Corsair replaced all my RM1000's with HX1000's for free. If I can remember you needed to look/view the PSU serial number to make sure it wasn't a "defective" model. At least a place to start. This is why in the end I'm using Seasonic PSU's. Still using the HXi's, which are made by Seasonic. Good luck.
