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Limiting the MAX fan speed on the MBA via smcFanControl

MayaTlab said:
Hi, I would like to know if I can set the fan up so that they won't rotate over 2500 rpm and not just 4000 rpm. Is it possible ? It seems the command line for 4000 rpm is "3e80". Should I write "2e50" ?

I ask this question because I am very sensitive to noise and really bothered, even at 4000 rpm. And since I have changed the thermal paste and use coolbook I intend to limit the maximum temp at 80 degrees (even if it means that the processor would have to slow down, because the stuff I do on my MBA is not processor intensive).

Thank you for your answer !
Click to expand...


Use these settings for the ff rpm
6200 - 60e0
5600 - 5780
5000 - 4e20
4800 - 4b00
4000 - 3e80
3600 - 3840
3000 - 2ee0
2500 - 2710

However, I would not set it at 2500. its might just be asking for trouble.
 
MayaTlab said:
Well, I have not been able to determine the hexa code for 2500 so I am currently at 4000 rpm, encoding a DVD with Handbrake. The CPU temp is 76 degrees and the Heatsink 63 degrees. I use CoolBook to throttle down the CPU to keep the temp under 75 degrees, so now my CPU is at 800 mhz, which is fine for me : why would I need handbrake to be faster if I encode during the night ? Moreover, with the fan set at 4000 rpm I can sleep while encoding 🙂.
Click to expand...

Thanks for the response. If limiting the fan can push the temp to 75 degrees, i don't think the computer is usable to 2000 rpm? it will either be too hot or you will have to go to 600 mhz or even lower to keep the temp down? as msinco has kindly posted the values for different, i'd be curious of your temp when the fan is set at 2500 rpm max.😀
 
I will try this soon.

However, I would like to say that, before tweaking my MBA, my CPU temp easily reached 85 degrees while throttling at 800 mhz, with the fan at 6200 rpm (I never had any CPU core shutdown though), so I have not lost any power but gained silence.

Oh and thank you msinco 🙂.
 
I tried the command in OP but it gave me this error:

smc command not found.

anybody knows how to resolve it? i tried both smcFanControl 1.x and 2.x version, tried the command with and without the app running, same result.

thanks for the help in advance!
 
bump i have my max fan speed set at 4600RPM. my temperatures never go that high anyways, so there is no need to have 6200RPM as default. The only time I need 6200RPM is when I stress test the machine to ensure stability. However, when I do that, I just boot into windows xp and everything is back on default. This coupled with coolbook has made my mba much more enjoyable.
 
All right, after a very busy month I have now set the fan at 2500 rpm all the time. Here is my "set up" :

First, I replaced the thermal paste for a bit of Arctic Silver 5 (not the best but I know it well). After calibration, I gained something like 2 to 5 degrees (good enough in my opinion). However, now the heatsink is in direct contact with the CPU and the graphic Chipset (and therefore tends to get slightly warmer than before, but that's a sign of better heat dissipation).

Second, I installed CoolBook. I discarded the 1600 Mhz setting because the CPU used to throttle down before installing CoolBook (to lower the temp) under heavy load. I just kept 800, 1200 and 1400 (setting it to 600 for battery life purpose is unnecessary in my opinion since CoolBook prevent us from lowering the voltage under 0.9v). All of them are set at 0,9v (no kernel panics for the moment). I set the maximum temp at 70 degrees so that CoolBook throttles down if necessary (I never asked to have a powerhouse anyway). The throttling level is set to "high" in order to watch H264 movies without scatters.

And finally I wrote a Script with Automator that launches after login and that set the maximum rpm at 2500. The same script is also used with SleepWatcher so that it also launches after sleep. Finally I wrote two other apps to set the fan at 4000 and 6200 rpm if necessary.

My temps under a very heavy load (Handbrake encode) are : 75 degrees for the CPU (CoolBook seems quite "flexible" and does not strictly respect the set temperature), 68 for the Heatsink.

And I can now "enjoy the silence" 🙂.
 
MayaTlab said:
And finally I wrote a Script with Automator that launches after login and that set the maximum rpm at 2500. The same script is also used with SleepWatcher so that it also launches after sleep. Finally I wrote two other apps to set the fan at 4000 and 6200 rpm if necessary.
🙂.
Click to expand...

I just downloaded SleepWatcher-package, but could you please post the commands you used to program so that the automator script launches after sleep?

Would be greatly appreciated!! 🙂

I´ve installed sleepwatcher and sleepwatcherStartupItem, but what to do next? Do I just need to put my automator-scripts in a certain folder?
 
MayaTlab said:
And finally I wrote a Script with Automator that launches after login and that set the maximum rpm at 2500. The same script is also used with SleepWatcher so that it also launches after sleep. Finally I wrote two other apps to set the fan at 4000 and 6200 rpm if necessary.

And I can now "enjoy the silence" 🙂.
Click to expand...

Very nice. I assume the scripts are for smcFanControl. You might want to post your scripts to save work for others... TIA.
 
Scott6666 said:
Very nice. I assume the scripts are for smcFanControl. You might want to post your scripts to save work for others... TIA.
Click to expand...


That I can do:


Go to Automator choose: custom/shell procedure/ delete "cat"/ insert text below / save as app

6200 max:
/Applications/smcFanControl.app/Contents/Resources/smc -k F0Mx -w 60e0

4000 max:
/Applications/smcFanControl.app/Contents/Resources/smc -k F0Mx -w 3e80

Or one of these speeds

6200 - 60e0
5600 - 5780
5000 - 4e20
4800 - 4b00
4000 - 3e80
3600 - 3840
3000 - 2ee0
2500 - 2710

Go to accounts in settings, and in startup items choose the script-app you´ve saved from automator, choose startup hidden if you like. I´ve put several scripts in a stack on the dock, so I can easily switch between different settings depending on my work scenario. Actually I never need to use 6200RPM-script (as there is very little different between this and 4000 RPM in practice). This gives me almost a noiseless MBA, sweet! 😀
 
SleepWatcher uses Unix executables placed in your Home directory. It is totally different from Automator scripts or Startup items, though the command lines are almost identical (this is why I made a mistake in my previous post by telling you that I "used the same script with SleepWatcher", sorry 🙂).

I use SMC Fan Control to get to the MacBook Air's SMC settings, so the command line only works with this method. I actually don't use the application itself and the following method is still worth a reading even if you are using a different method to access the SMC settings (you will just have to change the path of the command line).

To create such an executable, open textedit and type :

#!/bin/bash

And on the next line the script you would like to execute.

It gives me :

#!/bin/bash
/Applications/smcFanControl.app/Contents/Resources/smc -k F0Mx -w 2710

Same line as in Automator (to set the maximum fan speed at 2500 rpm).

Then, still in textedit, open the menu "format" and clic on "convert to text file". You should see now a very ugly kind of font (perfectly normal 🙂).

Save your text in your Home directory (not elsewhere) as ".wakeup" (with the dot but without the quotation marks). You cannot call it differently (that's the way Sleepwatcher works). Because it has been saved with a dot before the actual name, it is considered a hidden file. It is not necessary to reveal it but if you really want to feel secure use a software to reveal hidden files (I personally use Onyx).

Now open the Terminal and type :

chmod +x /Users/YOURHOMEDIRECTORY'SNAME/.wakeup

of course change YOURHOMEDIRECTORY'SNAME into your home directory's name 🙂.

Normally the text file is now a Unix executable and has a totally new and much better looking icon.

Please tell me if there is any mistake here, I'll correct them as soon as possible.
 
But how do I see hidden files in Onyx, you mean using the "find"-app under /utilities?
Click to expand...

You should go to "preferences", then "finder" and you should see an option to reveal hidden files.

Don't worry Onyx won't mess up with any of your mac (a very neat app 😉).
 
MayaTlab said:
You should go to "preferences", then "finder" and you should see an option to reveal hidden files.

Don't worry Onyx won't mess up with any of your mac (a very neat app 😉).
Click to expand...

Thanks! Now all I need to do is reapply the thermal paste (without breaking the machine) and I´m all set for a perfect MBA 😎
 
MayaTlab said:
Well, I have not been able to determine the hexa code for 2500 so I am currently at 4000 rpm, encoding a DVD with Handbrake. The CPU temp is 76 degrees and the Heatsink 63 degrees. I use CoolBook to throttle down the CPU to keep the temp under 75 degrees, so now my CPU is at 800 mhz, which is fine for me : why would I need handbrake to be faster if I encode during the night ? Moreover, with the fan set at 4000 rpm I can sleep while encoding 🙂.
Click to expand...

I don't know the code for 2500, but at another blog, someone suggested setting the minimum to 1500. The code for 1500 is F0Mn.

Here is the link to that blog:

http://horstr.blogspot.com/2008/04/dont-throw-your-macbook-air-out-just.html
 
This works, thank you, thank you, thank you

I have just registered only to thank you everybody for this marvellous sollution. It's good to know that although Apple does nothing useful to solve his customers problems there are people that have clever ideas.

Thank you again and sorry for my bad english
🙂
 
lonboy said:
I have just registered only to thank you everybody for this marvellous sollution. It's good to know that although Apple does nothing useful to solve his customers problems there are people that have clever ideas.

Thank you again and sorry for my bad english
🙂
Click to expand...

No problem 😉
 
Man I feel really stupid but I cannot get this to work. Can someone make a quick video or help me out? I run Automator and follow the instructions. Save it as an app and have in launch at login. I have smcFanControl installed. The fans still run up to full speed when watching Youtube for 5 min +
 
The script used to work for me before. But not anymore 🙁
Is it due to a MacOS update or something else ?
Thanks for you help !
 
pgharavi said:
yes, my original automator script still works fine. I've attached it here.
Click to expand...

Thanks a lot for this pgharavi 🙂
Unfortunately, your automator script don't run on my MacBook Air 🙁
When I double-clic on it, I can see very briefly something like a red circle appearing in my menu bar (informing that the script is running) but it has no effect on the rpm when I check in iStat, for example.
It is a complete mystery since this automator script was running very fine before (before what is what I am trying to know).
A few questions :
- Do the smcfancontrol application has to be launched (or launched at startup) to make the script work ?
- Is you smcfancontrol.app at the first level of the application folder (or inside the "smcfancontrol2.1.2" folder) ?
- Would I have to reset smc, pram or something else ?

Any other idea to solve the problem ?

Thanks for your help !!
 
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