bought a s9 off craigslist and not sure if it's defective or if I'm just a noob

[madkao]

first time jumping into mining and the TH are all over the place.   Nice hash has me mostly around 6TH but sometimes it will spike to 14..   Is that normal?   attached is a screenshot of the status of the miner


https://www.dropbox.com/s/hvuqsolivjj7bjx/Screenshot%202017-12-02%2009.06.12.jpg?dl=0

any info would be appreciated

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[VRobb]

Looks like one of your boards is only hashing at 10% of rated. What psu is powering this?

[madkao]

have 2 hp 1200 watt power supplies connected to it that he included

[HagssFIN]

You seem to have one faulty hash board in the Chain 4.

[VRobb]

You should have plenty power, have you tried moving the connectors around and see if the problem follows? Hash boards are usually running or not, that kinda running is strange!

[HagssFIN]

Yeah.
And make sure you don't mix those two psu's in the same hash board!

[madkao]

ok so that could be it...   each psu was set up with 5 outputs so one is sharing

[HagssFIN]

If you connect two psu's in the same hash board, the psu's might start to "fight" each other and the result is not pretty.

USE ONE HP DPS 1200 PSU FOR TWO HASH BOARDS.

AND THEN USE THE OTHER ONE HP DPS 1200 PSU FOR ONE HASH BOARD AND THE CONTROLLER.

[HagssFIN]

And first power on the psu powering two hash boards.

After that you power on the psu powering one hash board and the controller.

[madkao]

so I just switched it over and there is no change     Any other ideas?

 If it is a faulty has board is there a way to buy a replacement or repair it?

also looking at the status, it looks like that hash board has 8 less asics than it should

[HagssFIN]

See this miner servicing guide by Bitmain. https://shop.bitmain.com/workOrderGuide.htm

There are separate instructions for warranty and for out of warranty repairs.

Please follow the instructions in the guide and contact Bitmain to start the repair process.

[cableiso]

I'd contact the seller immediately.  That device also has a lot of hardware errors for only running 20min.  Is it filled with dust?

[madkao]

unfortunately I think I'm screwed...  bought on craigslist and he only responded through there...  have no contact info

[cableiso]

Tell CL you were scammed they have his real email at least


Edit: you could also try disassembling it and blowing dust out of the hashboards with compressed air.  Be careful not to knock any of the heatsinks.

That fixed the hw errors on one used unit I had.  And sometimes just switching the boards positions can improve things.

I doubt you can revive the bad chips, but it looked like only a handful on one board, meaning you could get 90% performance if the hw errors could be improved.

[fanatic26]

If you had a board with shared power connectors im betting thats the damaged one. This is, for the billionth time, why you do not buy miners from random people.