Antminer S9 : 1 board running hot - worth rearranging?

[Tomintx]

Antminer S9. I am feeding this thing with a small A/C unit to keep incoming air about 60-65 degrees F.

One of the boards is reporting consistently hotter than the others.  PCB/Chip temps are 52/85, while the other 2 are running 49/78. 

Is one board running hot because of its position, or is it worthwhile to rearrange these PCBs?

Also like to know how hot is *really* too hot.  80C is the stated limit, but some chips out there can run all the way to 125C without damage.

Thanks.

[1713586331]

1713586331

[wmabern]

Antminer S9. I am feeding this thing with a small A/C unit to keep incoming air about 60-65 degrees F.

One of the boards is reporting consistently hotter than the others.  PCB/Chip temps are 52/85, while the other 2 are running 49/78. 

Is one board running hot because of its position, or is it worthwhile to rearrange these PCBs?

Also like to know how hot is *really* too hot.  80C is the stated limit, but some chips out there can run all the way to 125C without damage.

Thanks.

One board on each of my four S9's constantly runs hotter (with high HW errors) than the others. It's the 3rd board, but marked Chain 4.
All of the S9's I have seen pictures of or have heard talked about seem to have this issue on that board.

It is probably a combination of miner body design, chip set / cooling fin placement, and just normal plain-old Bitmain slack-assed-ness for not fixing a problem before it left the factory. I'm sure they were aware of it.

But people like me (and others) continue to buy their flawed equipment to keep up with the Joneses. 

[NotFuzzyWarm]

Antminer S9. I am feeding this thing with a small A/C unit to keep incoming air about 60-65 degrees F.

One of the boards is reporting consistently hotter than the others.  PCB/Chip temps are 52/85, while the other 2 are running 49/78.  

Is one board running hot because of its position, or is it worthwhile to rearrange these PCBs?

Also like to know how hot is *really* too hot.  80C is the stated limit, but some chips out there can run all the way to 125C without damage.
Thanks.

And in how many threads does this have to be asked/answered?? Read a little before asking folks...
https://bitcointalk.org/index.php?topic=1559410.msg15677641#msg15677641

Also, unless you have free power, odds are that lil' AC unit is eating most/all profits from the miner...

[alh]

I think that there is little value in trying to get a uniform temperature across the 3 blade, give the current tube design. As long as the cool boards aren't too cold, and the hot board isn't too hot, you should probably just get used to a temperature variance. The 3 boards don't all get the same amount of consistent airflow across the heatsinks. Similar yes, but different enough to result in different temperatures.

[talks_cheep]

I think he should open up his S9 and re-arrange the boards. If the new arrangement results in chain #4 again running hotter, that should definitely prove the defective BMT engineering.

OP, please feel free to re-arrange the boards.

[edonkey]

I think he should open up his S9 and re-arrange the boards. If the new arrangement results in chain #4 again running hotter, that should definitely prove the defective BMT engineering.

OP, please feel free to re-arrange the boards.

Honestly I think there's not much value in doing this. There's tons of reports of "hot 4th chain" syndrome. My S9 is the same.

It is probably an airflow design failure, but it's also extremely unlikely that Bitmain will take any action, regardless of whether the OP proves the problem or not.

Better to live with it and not void his warranty.

Maybe it would be more effective to start a poll thread where people who have S9s vote about the hot 4th problem. If enough people vote and it's overwhelmingly evident that the 4th chain is in fact problematic, then maybe, just maybe, Bitmain might notice.

[NotFuzzyWarm]

I think he should open up his S9 and re-arrange the boards. If the new arrangement results in chain #4 again running hotter, that should definitely prove the defective BMT engineering.

The hotter board caused by the lower airflow there is not 'defective engineering'. It was an accepted design choice. Since the boards in that location do work acceptably well then form-factor overrides perfection.

Perfection is not only unneeded for most things, it is also usually very expensive to build. Part of Engineering is learning the very gray area between, "Well, it works" and "it works perfectly in all ways". Most often the final product will fall somewhere between those two points. For consumer goods the roadblock on the path to perfection is usually Marketing ideas of what that (perfection) is and cost.

Now if we start seeing failures of that board more often than the others, then you have a case.

[philipma1957]

Hot fun in the summer time!

A) op you do not need the make the gear 49/78

B) if you turn the ac off you will save quite a bit of power.

C) simply down clock the freq from where it is by 50. Ie 600 to 550

The power saved from the ac turned off will make up for the downclock.


The temps should be more like 60 /90   With the down clock