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hi All, my A741 is running at Temperature 45-50 / 98 - 100, with 100% fan speed and -1 Power. Anyone know what's the maximum allow for this machine?

What's your temperature ?

i forget the link ...
but i have read until 105 celsius, 221 fahrenheit, all still ok.
but you are really near this temperature ...

yes, im very near and im thinking it's not good to the miner. Maybe im writing to Avalon asking for real data.

I ran my Ant miner at 65-70c for over a year.. if that puts you at easy at all..

for antminer, im running 70-75 without a problem for 2 year++, as im new to Avalon, i dont have any data on this.

What is the 39/91 tempature mean is one ambient and one core?

The way the miner stats show it that is the inflow and outflow temperatures of the Miner air. I always assume they are what the temp is on the board at inflow or outflow, but I can't be sure.


OP: You will want to do something to either exhaust the hot air your miner is creating or find a way to introduce cooler air to your miner intake. What is your setup like?

I'm pretty sure the specs call for operating in ambient air not warmer than 40 C.

Good luck

So what would you suggest the safe range for input and exhaust temps are for avalon 741

A nice range would be keeping your ambient temperature between 15 and 30 C, if you can. I've only been running the units for a few months but I find these are a good range. It allows wiggle room if it warms up a few degrees or also if it cools down. I found my performance dropped off a little when my ambient air got around 5 C, and if it gets over 30 C, my fans are running at 100%, and the outflow reads in the 90's.

I like to see my outflow below 90C because I'm paranoid and like to know I have wiggle room, other things that will affect it is if you have a dusty/buggy environment because this will reduce cooling.

Obviously my numbers are not hard and fast but it's what I'm shooting for for the time being.

yeah i got my intake down to 32-35 and exhaust down 85-95 range i ordered some more fans coming in tomorrow and im gonna move my gpu rigs out of that room also they make the ambient temp a lot hotter. any one will a good feasible idea ill send a small tip i live in south texas so outside air is usually hot i keep my ac on 67-68 though

set to -2

 the 45-50    is above spec  that is the inside board temp



the 98-100 is very close to max



how hot is the room?

The room when gets about 30 c when everything’s running I’m getting better cooling tomorrow but even when it’s at those temps fans only at 93% it dosnt go to 100% till I take is over 41 c

Ambient temps don't seem incredibly bad, you likely just don't have good airflow in the room. Try getting a box fan or any sort of fan and getting air in and out of where you are mining. I'd try underclocking to reduce power usage. Sounds like the chips at the back of the miner are getting absolutely burned right now.

alright put it to -1 I didn’t really wanna do that because as hot As it was at 0 it was hashing at an average of 9 th/S according to the controller and the daily average on the pool

I have a shop fan behind it and a shop fan on top blowing down I do get a DH if 1% after like 12 hours Idk if that’s normal.

Do you have a window in the area that you are setup, your best option is always to get the exhaust from the miners out of the room.  If you can move them closer to the window and have them exhausting towards it that will help you out tremendously.

If you have just the one 741 you could put all your rigs near the window and use one of your fans as an exhaust fan.

This way your house AC is only working as hard as it normally would be and you won't have to cool the Miner exhaust air.

If there is no window, can you describe the type of room you are mining in, might be able to help with a better idea.

its a medium small room with 2 gpu rigs and 1 avalon it has a window the window is open and the door is open right now its a square room. i ordered a window fan coming in tomorrow i was planning on pointing the avalon towards the window with the fans blowing out. i have a small fan and a shop fan in there right now. with the undervolt its at 35/89 after an hour. the DH is up to 2.1 % is that acceptable? it never went over 1.8 at 0. fan is at 90% on the miner tomorrow my other psu will be here also to hook up second miner they are running on 220. the gpu rig all gpu's are running under 62 c i switched from ethereum to zcash that dropped the gpu temps in turn dropped the room temp. i was thinking more fans? or do you have a better suggestion. winters coming which is good but its texas so it can 30 degrees today and 90 tomorrow still. you have a certain fan you recommend? any suggestions would be appreciated i can send u a small tip for ur help if u send me a bch, litecoin, or ethereum address.

I don't really have a certain fan I recommend, before it hit Winter here in Canada, I was running 2 741's in my garage and I was just using a vertical window mount fan exhausting and that seemed to do the trick just fine, but it was a large garage.

https://www.homedepot.ca/en/home/p.thin-black-window-fan.1000803277.html

This is what I was using.

The nice thing is you can fit 2 or more of them in a window if you need to to increase how much air you need to exhaust from the room. They might be nice to use because you also have the GPU rigs adding heat to the space. In this case I would have the miners back about 1 1/2 feet from the window.

I don't know much about the GPU mining so I'm lost on helping with suggestions for that.

If I were just now setting up my 2 Avalon 741's in my garage, similar setup to you, I would place them both very close to the open window (6-12 inches) exhausting out, with a fan blowing towards them and the window.

If you expand further then I would look into getting a larger barrel fan or something to mount on the window itself for exhaust.

Hope that helps.

I ordered a window fan that blows out the window like an exhaust fan set them facing the fan with a large shop type fan behind and under voltage set to -2 and now it’s readinf 37/88 with the door to the room shut for 12 hours during the day. And it was about 76-80 degrees outside today... is that in a decent range it runs cooler with door open but I can’t leave the door open 24 hours a day due to my daughter but it stays open 75% of the time. I just wanted a test run at worst possible scenario.

That's still within range for sure does it tell you if your fan is runni f 100%. You wouldn't want it to get any warmer in the room, but if that was all day, and you can periodically open the door to bring down the temperature you should be fine.

Yeah I checked it every 20-30 minutes and that was max fan stayed about 80-87% sometimes hit 100% but rare... it’s hashinfg faster now and running cooler but now
My DH is over 3 is that something to worry about ?

Okay I am escrowing a sale of 2 avalon 741's


I think one of them has an issue.

one is in a 70-75f room

temps look good

https://i.imgur.com/c4ktccF.png



the other is in a 60-65 f room 

temps are higher and intake is lower

 https://i.imgur.com/1tH4uPb.png

To me  one is a pretty good unit.  Is it set to -2 or -1 ?
It can safely go up 1 number.

Move from -2 to -1  or
from -1 to 0


The other is a bit concerning  is it at -1  if so drop to -2 .
So does the buyer want a discount or a return on the hot one?
Was it used was it new?
Did it come from the USA  seller minerwarez?


I see the intake number of 27  that is a good number.
I see the chip at 101 that is borderline.

I linked the photos to another thread asking a 15 unit owner his numbers.

https://bitcointalk.org/index.php?topic=1673843.msg25493815#msg25493815

I'm sure you've already checked that the fan is blowing the right way on that unit, I remember there was the one person who had one mounted backwards. I guess if that was the case your intake temp would be higher.

Did the seller clean the unit up before sending it along? It might just be that it caught some dust or an insect or 2 inside. Looks like something is definitely restricting the airflow somewhere.

Did the seller have any snapshots of the units running before sending them along? Maybe they had the same issue.

yeah  that could be the issue  the fan  is pointed wrong


these came sealed from the  minerwarez  company

Has anyone seen oscillation in the 741 temperature/hashrate?  Meaning that hashrate creeps up over time to some point at which the temperature spikes, causing the fan to peg to 100% and HW errors backing down the hashrate..  Then it repeats.  The one I'm looking at has a freakout about every 30 minutes.  Voltage offset is -2, frequency is nominally 702MHz and hashrate about 7.2T.

I remember Steve from Canaan, talking about the way the miner hashes causing it to oscillate sort of like that. If the chips can they work harder to a certain point, and then when the failures/rejects start to climb it ramps back down.
I don't remember it really tying into temps to much, but if it is overheating you would probably get the same result.

What are your temps like on the Miner status? What is the rooms ambient temperature? Is there a reason you went with -2 offset?

My 741's have a pretty wide range in hashrate between the 2 of them but at 0 they average out to about 7.8 TH/S



Glad you found the issue, it seems a few have snuck through QC, I guess in a Data center the airflow must be enough to keep them running cool

Which side is suppose to intake and which side is suppose to be exhaust on avalon? Is the fan suppose to pull through the unit or push air through the unit? Because mine blows hot air out the side the fan is on.

That sounds right, the fans pull the air through the unit and exhaust the air on the side the fan is mounted.

In      the side the cables are connected
Out     the side the fan is mounted