Antminer S7-LN Troubleshooting/Repair/Parts Help

[ATC_Rob]

I purchased a couple Antminer S7-LNs from a seller on eBay this week. One of the miners showed up overclocked to a frequency of 825 with the fan set at 45%. As soon as I accessed the online interface, I bumped it down to 600 and fan to 95% to get a baseline. It was running and staying in the 50-60 degree range for about 24 hours and then I got some XXXOOOXXXOO errors. I rebooted the machine and the errors went to the dashes -------------. Since then only 1 board has worked and the temp on the bad board is showing around 29 degrees. The other board that is running works great.


Where is the best place to order a replacement board and replacement fans? I could not find the board on Bitmain's site.
I have read online that it could be a bad PSU or bad board.


Any suggestions or links will be greatly appreciated.




Update: I have been troubleshooting all day (unplugging, letting it sit, changing frequencies and fan speeds) and sometimes I get all 0000000000000's on the board with no hashing. Sometimes all Dashes ----------------. And sometimes all XXXXXXXXXXXXXXs. No rhyme or reason to the board at all.

[flameruk]

Try swapping io card between miners first, to determine if hash cards at fault or controller.
I’ve replied to you on Reddit.

[ATC_Rob]

Thank You!  I will try it today.

[fanatic26]

It sounds like the person you bought them from had a crazy overclock running. Its no surprise that one of your boards has failed. You should never overclock this stuff, its just asking for failure.

You will not be able to buy a 'new' replacement hashing boards specific to the LN as the S7-LN wes a 1 off production run over a year and a half ago.