BFL Single air flow? - page 3. | Bitcointalksearch.org

ewibit

legendary

Activity: 2955

Merit: 1049

is it possible that my BFL LS has this problems because airflow?

Code:

2013.09.09 [17:11]  BitFORCE (ttyUSB0) ERROR: Unexpected response without command: BitForce SHA256 SC 1.0 
2013.09.09 [17:11]  BitFORCE (ttyUSB0) ERROR: Command timed out. Retries: 0 
2013.09.09 [17:11]  Probe of port /dev/ttyUSB0 failed: timeout 
2013.09.09 [17:13]  BitFORCE (ttyUSB0) ERROR: Unexpected response to work results poll command: BitForce SHA256 SC 1.0 
2013.09.09 [17:13]  BitFORCE (ttyUSB0) ERROR: Unexpected response to temperature check command: INPROCESS:1 
2013.09.09 [17:13]  BitFORCE (ttyUSB0) ERROR: Unexpected response to temperature check command: COUNT:16 
2013.09.09 [17:13]  BitFORCE (ttyUSB0) ERROR: Unexpected response to temperature check command: 283DF32FA7E2E8C4E19BFDFC0E59355142FF2A3B01C658891AD9D0743EEA14A2,B7C23A1A522DE58E1931679C,5,1,6BC1B0FE 
2013.09.09 [17:13]  BitFORCE (ttyUSB0) ERROR: Unexpected response to work queue flush command: 283DF32FA7E2E8C4E19BFDFC0E59355142FF2A3B01C658891AD9D0743EEA14A2,B7C23A1A522DE5981931679C,2,3,1B251CAF,28F291D5,B0A3BE86 
2013.09.09 [17:13]  BitFORCE (ttyUSB0) ERROR: Unexpected response to queue job pack command: 283DF32FA7E2E8C4E19BFDFC0E59355142FF2A3B01C658891AD9D0743EEA14A2,B7C23A1A522DE59D1931679C,0,2,66804588,851B4256 
2013.09.09 [17:13]  BitFORCE (ttyUSB0) ERROR: Unexpected response to queue job pack command: 283DF32FA7E2E8C4E19BFDFC0E59355142FF2A3B01C658891AD9D0743EEA14A2,B7C23A1A522DE59C1931679C,7,0 
2013.09.09 [17:13]  BitFORCE (ttyUSB0) ERROR: Unexpected response to temperature check command: 283DF32FA7E2E8C4E19BFDFC0E59355142FF2A3B01C658891AD9D0743EEA14A2,B7C23A1A522DE5A21931679C,4,0 
2013.09.09 [17:13]  BitFORCE (ttyUSB0) ERROR: Unexpected response to temperature check command: 283DF32FA7E2E8C4E19BFDFC0E59355142FF2A3B01C658891AD9D0743EEA14A2,B7C23A1A522DE5AC1931679C,3,1,E9C671B0 
2013.09.09 [17:13]  BitFORCE (ttyUSB0) ERROR: Command timed out. Retries: 0 
2013.09.09 [17:13]  Probe of port /dev/ttyUSB0 failed: timeout

it stops after ~1-2 hours and is not starting automatically again (exept for starting BitMinter client manually new)
(I have removed the inflow plate because with this it is much louder and stops quickier)
TIA

JimiQ84

sr. member

Activity: 406

Merit: 250

Quote from: Bicknellski on September 09, 2013, 06:13:37 AM

Let us keep it simple. Does the unit have temperature sensors? Are they showing better cooling? Are you getting better hashrate?

If you are good enough.

I'd say temperature is the same and power usage is some 2-4W lower

Bicknellski

hero member

Activity: 924

Merit: 1000

Let us keep it simple. Does the unit have temperature sensors? Are they showing better cooling? Are you getting better hashrate?

If you are good enough.

eestimees

hero member

Activity: 651

Merit: 500

Quote from: dogie on September 09, 2013, 05:51:50 AM

Non steady state conditions tell you nothing about the cooling capacity of the system, too many things going on.

And by that you mean? Sorry but english is not my 1st language.

dogie

legendary

Activity: 1666

Merit: 1185

dogiecoin.com

Quote from: eestimees on September 09, 2013, 05:37:22 AM

Quote from: dogie on September 09, 2013, 05:21:51 AM

Quote from: eestimees on September 09, 2013, 03:56:38 AM

we'll see when i get the thermal cam in my hand, we'll see... I only need to figure out how to take pictures so that metal case would not block my "heat view".. I mean, I can't take pics when cover is taken off.. then the air will not tunnel through.. and taking pics with cover on I cant see single component heat.. I can only see heat spots on case.. maybe that is enough though...

Thermal cam won't particularly help. Just look at core temps at a fixed ambient and fan rpm.

as I think I mentioned before, "my design" appear to push out less air, and hashing temp is the same (although reaching same temp takes more time) = less rpm needed to cool to same temp, but that's not all, shutting down miner and starting again show that modified single has cooler starting temp = it must be more efficient as air goes thru single and does not hassel around-up-n-down (also less noisy), now i order to see if everything is cooled and compare original design with my design I was thinkig of takeking thermal images where both are in front of me on the table, and outside (to get bigger contrast of cold/warm).

Non steady state conditions tell you nothing about the cooling capacity of the system, too many things going on.

eestimees

hero member

Activity: 651

Merit: 500

Quote from: dogie on September 09, 2013, 05:21:51 AM

Quote from: eestimees on September 09, 2013, 03:56:38 AM

we'll see when i get the thermal cam in my hand, we'll see... I only need to figure out how to take pictures so that metal case would not block my "heat view".. I mean, I can't take pics when cover is taken off.. then the air will not tunnel through.. and taking pics with cover on I cant see single component heat.. I can only see heat spots on case.. maybe that is enough though...

Thermal cam won't particularly help. Just look at core temps at a fixed ambient and fan rpm.

as I think I mentioned before, "my design" appear to push out less air, and hashing temp is the same (although reaching same temp takes more time) = less rpm needed to cool to same temp, but that's not all, shutting down miner and starting again show that modified single has cooler starting temp = it must be more efficient as air goes thru single and does not hassel around-up-n-down (also less noisy), now i order to see if everything is cooled and compare original design with my design I was thinkig of takeking thermal images where both are in front of me on the table, and outside (to get bigger contrast of cold/warm).

dogie

legendary

Activity: 1666

Merit: 1185

dogiecoin.com

Quote from: eestimees on September 09, 2013, 03:56:38 AM

we'll see when i get the thermal cam in my hand, we'll see... I only need to figure out how to take pictures so that metal case would not block my "heat view".. I mean, I can't take pics when cover is taken off.. then the air will not tunnel through.. and taking pics with cover on I cant see single component heat.. I can only see heat spots on case.. maybe that is enough though...

Thermal cam won't particularly help. Just look at core temps at a fixed ambient and fan rpm.

eestimees

hero member

Activity: 651

Merit: 500

we'll see when i get the thermal cam in my hand, we'll see... I only need to figure out how to take pictures so that metal case would not block my "heat view".. I mean, I can't take pics when cover is taken off.. then the air will not tunnel through.. and taking pics with cover on I cant see single component heat.. I can only see heat spots on case.. maybe that is enough though...

Bicknellski

hero member

Activity: 924

Merit: 1000

Quote from: dogie on September 09, 2013, 03:10:00 AM

Quote from: Bicknellski on September 09, 2013, 02:17:46 AM

If it works great job.

Guessing the venturi effect is helping move that heat away nicely.

*Around the heatsink through the massive 0 resistance gap, yup. No way that is cooling better than before.

Evidence to support your theory it doesn't work, possibly some models or math to prove that?

Basically calling the guy a liar, I am pretty much inclined to give him the benefit of the doubt at this point given the inelegant solution that was devised by BFL in the first place. Time for some numbers and proof cause dogie is calling you out eestimees.

dogie

legendary

Activity: 1666

Merit: 1185

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Quote from: Bicknellski on September 09, 2013, 02:17:46 AM

If it works great job.

Guessing the venturi effect is helping move that heat away nicely.

*Around the heatsink through the massive 0 resistance gap, yup. No way that is cooling better than before.

Bicknellski

hero member

Activity: 924

Merit: 1000

If it works great job.

Guessing the venturi effect is helping move that heat away nicely.

eestimees

hero member

Activity: 651

Merit: 500

here it is

and still i'm pretty sure it is not only quieter but efficient too. still thermal imaging to be done to measure temp under the board and so.

dogie

legendary

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Quote from: eestimees on September 08, 2013, 08:03:17 AM

Got my singles, today i moded one as i described, and it feels to me that it is more efficient. They are both side by side, hashing 61-63C. When i stop miner and start again, the modded single temp is much lower than original cooling setup. Within few minutes, they both are at the same temp again, but it feels like modded one's airflow is ligther = fans rotating slower.

Tomorrow i upload some pics of how i did it. I will try to get something to measure airflow and friend said he can borrow thermal cam to take pics.

tldr: You won't be able to get anything that measures airflow to any meaningful precision, unless you have a venturi arrangement.

eestimees

hero member

Activity: 651

Merit: 500

Got my singles, today i moded one as i described, and it feels to me that it is more efficient. They are both side by side, hashing 61-63C. When i stop miner and start again, the modded single temp is much lower than original cooling setup. Within few minutes, they both are at the same temp again, but it feels like modded one's airflow is ligther = fans rotating slower.

Tomorrow i upload some pics of how i did it. I will try to get something to measure airflow and friend said he can borrow thermal cam to take pics.

dogie

legendary

Activity: 1666

Merit: 1185

dogiecoin.com

Cooling is much better when blowing through rather than sucking through a heatsink. As others have said, it takes a worse path when sucking through. This is because the pressure profile on either side of the fan isn't the same, its much stronger and compact on the blowing side.

Additionally, the rest of the PCB and components need airflow that a sucking arrangement wouldn't provide.

chanberg

hero member

Activity: 672

Merit: 500

I have 4 Jalapenos, and I arrange them in a stack of 2 open case (so two stacks, one on top of each other). If I leave it the way it is, it runs about 40C, if i put two fans next to them in a push pull manner, they drop 6C to about 34... So the two fans do make a difference believe it or not.. Also the push pull config fans are pointed in the direction of the heatsink grooves..

ASIC-K

sr. member

Activity: 280

Merit: 250

Hell?

the small fans blow UP not down.

i have a single, and this is how it works.

crazyates

legendary

Activity: 952

Merit: 1000

Quote from: eestimees on September 02, 2013, 06:41:45 AM

Problem: The 2 smaller fans don't blow down. They blow up, IIRC. People who have been running them out of their case have been reversing the direction so the fans blow down.

I feel like it's an interesting idea, but IDK how well it will work. The heatsink has a significant gap between the actual chip and the heatsink itself, so I don't feel it would be completely effective.

I've actually heard that the noise can be cut down significantly by running it outside of it's case, and with 2 quieter fans replacing the heatsink fans, but blowing down.

Still, you've got to remember: dissipating 200+Watts of heat is not an easy thing to do, although I do feel that 4 fans is a big overkill.

k9quaint

legendary

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Quote from: bcp19 on September 02, 2013, 08:32:31 AM

Quote from: rupy on September 02, 2013, 07:29:39 AM

I think the best solution for sound here is remove the case and all fans, then place 2 singles next to eachother and put one big fan on top that covers all 4 heatsinks. Also why are all top mounted fans blowing DOWN?? Heat naturally goes UP!!

The heat will go naturally up... the fins of the heat sink. The narrowness of the fins combined with their height gives a lot of surface area for the radiation of heat off of the fins. Many Jalapeno owners have already stated that the stock position of the fan (blowing up, thereby pulling air through the fins) results in the system running several degrees hotter than if the fan is blowing down into the fins. It is much easier to get a uniform airlfow by pushing air than by pulling it.

When pulling air through a fan, it will take the path of least resistance into the fan. Thus it will not flow over the entire surface of the heat sink fins, but instead flow in along the top. Using the fan to push, thereby forcing air all the way down into every crevice of the heat sink creates airflow along the entire surface area of the heat sink which increases the amount of heat that can be transferred away.

bcp19

hero member

Activity: 532

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Quote from: rupy on September 02, 2013, 07:29:39 AM

I think the best solution for sound here is remove the case and all fans, then place 2 singles next to eachother and put one big fan on top that covers all 4 heatsinks. Also why are all top mounted fans blowing DOWN?? Heat naturally goes UP!!

The heat will go naturally up... the fins of the heat sink. The narrowness of the fins combined with their height gives a lot of surface area for the radiation of heat off of the fins. Many Jalapeno owners have already stated that the stock position of the fan (blowing up, thereby pulling air through the fins) results in the system running several degrees hotter than if the fan is blowing down into the fins. It is much easier to get a uniform airlfow by pushing air than by pulling it.

Topic: BFL Single air flow? - page 3. (Read 6924 times)