Earlier I noticed one of my miners, a Z9 mini, had dropped so I headed over to my mine to check it out. When I got there I noticed the miner was completely off, no lights, but the PSU fan was still spinning. I figured it was probably just a bad PSU so I went ahead and replaced it with a spare and set everything back up again to test. As soon as I plugged it back in, flames, sparks and smoke started shooting out the back of miner. It looked exactly like someone had lit a sparkler. I was able to unplug it quickly enough before it got any worse or anything else got damaged.

I’ve always been a little paranoid about a fire happening at my mine and this kinda shook me a bit. Not too long ago I bought these exploding automatic fire extinguisher balls and mounted them around my mine as a last resort incase a fire ever did break out. Im lucky it happened while I was there to quickly respond to it, otherwise I can imagine how things could’ve gotten out of control.

I’m not sure what caused the short but I’m guessing it might have shorted out originally and when I replaced the power supply and powered it up again it started to spark and burn.

I took some pics of the damaged board. I lost 2 boards in all.

https://imgur.com/gallery/8U7pnln

I did some googling and found one other case of this happening. Looks like it also shorted in the same location on the board as mine did.

https://thebitcoin.pub/t/z9-mini-burst-into-flames-fake-bitmain-warranty-poorly-built-hashboards/48430

Anyone know of any other cases where this has happened? It has me a bit worried about my other Z9 mini's and whether there is a defect in the board design itself.

I tested my 53TH/s pro on two separate banks on my PDU. Like yours my PDU only shows whole numbers and rounds up or down sometimes depending on the threshold. Together on the same bank both cords pull 11 amps on my 208v electric. When I plug each plug into their own bank my PDU’s show 5 amp draw per plug. I’m estimating it’s probably more around 5.5 amps so on 208v that would mean 1144 watts per plug. This is on normal mode so it looks like the PSU’s split the load evenly across the two plugs.

I’ve heard from someone who’s contacted Bitmain about this that the PSU splits the load equally between the two cords. So it should be, based on his reported numbers, 1025 watts per cord in normal mode and 1250 watts in Turbo.

I have the 53 TH/s model and my metered PDU’s, which only measure in amps, are showing ~11 amps total in normal mode on 208v power at 53-54TH. They also only show whole numbers and sometimes round up, so it’s not super accurate. That would put me at around 2288 watts or 1144 watts per cord.

This definitely sounds like it could be a bad Ethernet cable since there are no indicator lights lit on your Ethernet port. I would recommend swapping out a new Ethernet cable and seeing if that solves it.

Just a suggestion to try swapping out your ethernet cable. I've had a few of my S9's get stuck in a boot loop because of a bad ethernet cable.

Did you ever find your miners IP or find a solution? Im having the exact same issue with one of my Dragonmint T1's as well. Can't find the IP anywhere when scanning my network. I actually had this issue with another T1 first. It dropped offline today so I went to my farm to see why and couldn't find the IP address when scanning the network. I tried some basic troubleshooting and figured it could be a bad control board. I had a spare Dragonmint with a few bad hash boards that I use for parts so I swapped out the control board from that. My network must have assigned a new IP and I was able to log in and get that one set up. However, literally like a minute later I had another Dragonmint T1 drop offline with the same issue.   I could no longer log in to the miner with the IP that it previously had. I did a reset and scanned the network multiple times and have been unable to find it.

I haven't had a chance to run through any of these possible solutions for finding it. I don't have the patience for it tonight but Im wondering if it is maybe my router not having enough IP addresses allotted to assign. I have a pretty large farm at the moment and I just added a few more miners the past couple of days so maybe that is the issue.

Make sure you don't have a dead ethernet cable. I've had this boot loop happen a few times and it just ended up being a bad ethernet cable causing the miner to just keep restarting. The cables I bought weren't the best quality and I've had it happen more than once. Check the lights around your ethernet port and make sure they are lighting up.

Im curious to see what the larger z9 can be overclocked to and if they use the same chips as in these. Perhaps you're right maybe they picked the best ones for the z9 and used the rejects for the mini's.

I did have one mini from the first batch which has the same chip issue. I could only overclock to 550m before the middle board would drop out. My other first batch ones are all stable at 750.

So far my second batch ones are running stable at 675m for 10+ hours and getting 14-15 ksol which isn't too bad.

I don't know if this has been posted yet in this thread but you can overclock it by using google chrome to edit the frequency on the "Advanced Settings" page. The instructions are posted here in the description of this video.

https://youtu.be/XI31hHhvYzA

I've got mine running stable for the past few hours at 675m. I'm getting 14-15k sol. Any higher and I start to lose boards unfortunately.

Oh no. Sorry to hear it didn't work man.

I swapped the controller cable from a working T1 and the board is still dead. I'm starting to think it might just be a bad board.

Unfortunately I'll probably just have to send it off for warranty work.

I changed the performance back to "balanced" cause it's obvious it doesn't like the overclock, and I'm still getting the dead board unfortunately. I thought it may be a bad PSU so I swapped it out with a PSU (myRig) from one of my working T1's and same thing, dead board. Updated to the latest firmware and same result.

Tomorrow I'm going to try swapping the cable from the controller to the board and try to rule that one out.

Hey guys wondering if anyone has figured out a possible solution? I tried switching my T1's to performance mode and I'm getting the "Error - failed to recv spi data" on two of my machines. On one all hash boards are down and on the other one board is down.

tim-bc, when you staggered turning on the miners one at a time was it only on that circuit/pdu? I have other miners currently running on other circuits and I'm wondering if I need to pull everything and then power them on again one by one.