Bitcoin Forum

about a month ago I got a used S7 that has run ok for now. However i've had to reboot a couple of times and I suspect it's because it went over 80C and stopped.

I check the board temperatures and one is running at 70-71C while the other two boards are running at 62-63C. Could this be an indication the miner needs a dustoff ? I'm running it next to an S5 (about 4 inches apart) so my other thought is that maybe the S5 is generating heat that is conducting to the S7 board closest to it. The S5 boards are running at 56-65C.

Thank you for any help you can provide.

possibility that S5 is influencing the higher temperature but to rule that out, you can move S7 into another air conditioned room and power it up and check the temperature. 

If in colder air conditioned room and 1 pcb is showing still hotter temperature, then, time to open the unit and see if cleaning be needed.  We have seen many units with temperature problem had everything you can think of collected and saved on the hash PCB and inside the S7 case.

dust, human hair, animal hair, hairball, candy wrappers, parts of vermine, insects.  So dust off may help if that is the case.

If dust off and in the cold room and the temperature will not be resolved, then please check the intake fan, if it is spinning at at least 3600 RPM. 

if none of those solves the problem... then you probably have some chips or components that are degraded but still function.  At this stage, not sure if its cheap enough to repair or seek used S7 and replace the parts or let it go

Repair on S7 pcb can cost from $35-$85 range some are less and some are more. 

I can't move the S7 to another room but I can power down the S5 for a trial period. So I will do that first. As for the fans I just checked and they are running at 4500 rpm or so.

I have seen a lot of dust on the fans so I imagine there's dust on the inside. I saw a few videos on how to clean the S7 so I will take that up once the S5 power down test is complete.

As for repairs it's too costly for me to send it for repairs. Are all boards on an s7 the same? this way I could just get a new-er board and keep as spare.

if you see heavy dust, probably that be the cause.

replacement wise, depends on where you are located,may be cheaper to just buy a replacement PCB.  or other units.  PCB version or model needs to match as there are several versions of S7 exist

How do I know which PCB to get?

The thermal paste can go bad too,check that last by removing heatsink & cleaning & reapplying with the correct paste,ask around about what paste is recommended  ;)

There is no thermal paste in S7....

If you clean it and it still runs a little hot thats not really a big deal. Unless it is throwing a ton of hardware errors or crashing all the time just let it run a little hotter.

Looking at the exhaust end the board on the left will almost always be a fair bit hotter than the other 2. Reason is the air flow in that location. Same applies to the s9 and t9. Just the nature of the design. The only reason for the *almost* is because s9/t9 miners with auto-tune can change it if Vcore is higher/lower per-board.

Coulda sworn I saw folks cleanin & reapplying paste on S7 awhile back....my bad  ;)

There is thermal adhesive in S5+, S7, S7-LN, S9, R4, T9, L3 and L3+ heatsinks.

So today I got an alert that my S7 was offline, again! I couldn't go to turn it back on for almost 8 hours. Thanks to you and some you tube videos I had a pretty good idea that I had to clean it and how.

I finally went to my S7 and took it apart. There was caked dust along with some real life bugs that caused obstruction on the front end of the boards. One more than the others. I spent a whole bottle of compressed air cleaning it up inside out and took out each board and blew all the dust out.

Eventually I figured I got all the dust out that I could. I put it back together and turned it on. It wouldn't turn on at first but I figured out I hadn't plugged in the front fan first. Plugged it in and got it working fine.

Temps are now in the 50-60 range versus the 60-75 range that was before. I hope it can now work for months without stopping.

Thank you all for your help.