Avalon 741 set manual fan?

[subie]

Hello,

I was able to witness an Avalon 741 from a friend and the sound when the fan is running at 80% is very loud, when it starts up to 50%, the sound is not that bad, is there any way to set the fan to 50%?

Thanks

[1714060611]

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[1714060611]

1714060611

[1714060611]

1714060611

[1714060611]

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[NotFuzzyWarm]

Only by setting  -1 or -2 in the config.
Fan speed is directly tied to chip temps and that is tied to their speed/Vcore. Quiet at first because it is cold. Use -2, lower speed and quieter fans when at temp. Cool ambient temp greatly helps as well..

[subie]

Thanks NotFuzzyWarm, I will check ambient temp, is that the room temperature? I also found a post by philipma1975 creating some kind of enclosure that could work to lessen the noise.

[xutopia]

Actually though the machine seems to have a mind of its own you can suggest a maximum fan speed.  From what I gather though it only seems to affect the maximum startup speed as the Avalon will bring the fan to higher speeds if it detects high heat.

Now on to voiding your warranty!

First SSH into the machine using your password:

Code:

ssh root@192.168.0.100

Then edit the cgminer startup script.

Code:

vi /etc/init.d/cgminer

There is a line that looks like this:

Code:

AVA7_OPTIONS=" --avalon7-fan $_fan-100 --avalon7-freq $_cf $CHIP_VOLT $VOLT_OFFSET $SSP"

100 in there is the maximum fan speed

Code:

AVA7_OPTIONS=" --avalon7-fan $_fan-60 --avalon7-freq $_cf $CHIP_VOLT $VOLT_OFFSET $SSP"

Now exit the editor

Code:

:wq!

and restart the machine:

Code:

/etc/init.d/cgminer restart

Like was said above it is recommended you use the -2 flag to voltage to avoid overheating if noise is of concern. Lower fan speeds means higher heat... lower voltage helps mitigate this.

Another option is put the device inside a box and use a dryer vent tube to exhaust the heat.  Helps reduce noise by about 20db.  Another is to grab cold air from outside. Lower heat will reduce fan speed even more.  I had one Avalon running in a shed at 1200RPM for a while.

Good luck and remember I am not responsible for fires, destruction of property or warranty obstructions.