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Limiting the MAX fan speed on the MBA via smcFanControl

Still working for me

The script works fine in my MBA even after the updates though due to some reason I don't know has become unnecesary, now fans work properly going up and down depeding on the work I demand. When I open two videos, fans are at 6200 soon but when I close them fans go down quicklier than ever. Miracle?
 
does anyone know all the different code combo's to get different RPM's via the terminal command with smcFanControl? 4000 is nice but i'd like to go to something like 2500 to 3000 when doing simple web browsing but i don't know the algorith/code at the end of the terminal command. My temp sensor for my hdd is broken so unless i limit it, it will be blazing out of control. new sensor coming soon though.


EDIT: FOUND A SITE WITH THE DIFFERENT RPM COMBO'S HERE: http://iloapp.elvsaas.net/blog/www?Home&post=51
 
what is the hex for 1000 ?

I want to try putting 1000 for my mac mini late 2009 (fans are currently running at 1500)

thx
 
SMC control doesn't seem to have an effect on any fans on my aluminum imac 20 inch.

I really really need to slow down my fan as I damaged the logic board while carrying out an upgrade (stupid I know) and it means the LCD temp connector doesn't work.

This makes my iMac fan go full speed constantly and it's absolutely deafening - the computer is basically a write off unless I can slow down the fan and I really can't afford a new one.

I found a program called Imac Fan control:
http://www.derman.com/iMac-Fan-Control
it DOES work on my machine for increasing the hard drive fan speed and optical fan speed. Therefore I need to know how to reduce fan speeds using the iMac Fan control app.

I'd really appreciate ANY advice here as any fix is basically going to get me my machine back!

Many thanks for taking the time to read this.
 
Some Pointers

Thx for the great info!

To determine a hex value, take the desired fan speed x 4 then convert it. This can be run in Terminal, replacing "RPM" with the desired speed:
Code: 
perl -e 'print sprintf("%X", (4*RPM))'
Alternately, you can plug the result of 4 x RPM into this page:
http://www.statman.info/conversions/hexadecimal.html

To determine the fan speed from a hex code, use:
Code: 
perl -e 'print ((hex "HEXCODE")/4)'
Substituting HEXCODE with either '0x60e0' or just '60e0' will work. Or use the above URL and divide the result by 4.

On a MBA 1.8Ghz, turning the fan down to 2k rpm has the system running cooler, quieter, and on battery gained ~an hour in combo w/ CoolBook!

As they say, YMMV.
 
Easy fix if your right fan isn't responding..

I installed smcfancontrol on Lion on a late 2011 MBP (two fans) and ran the command. The left fan was regulated perfectly, but the right fan was not able to be controlled.

So I changed the "F0Mx" in the command line to "F1Mx" and ran that too. In other words, I ran these back to back in terminal:

/Applications/smcFanControl.app/Contents/Resources/smc -k F0Mx -w 3e80
/Applications/smcFanControl.app/Contents/Resources/smc -k F1Mx -w 3e80

Now both the left and the right max fan speed is regulated and my MBP is much, much quieter.
 
Limiting max fan speed, but on Mac Pro??

I've followed this thread to successfully set my max fan speeds on my MBP late 2011 and it has made a HUGE difference as I need to on occasion shut the MBP up when I have a vocalist in the room to record.

Now I have a new Mac Pro 2012 and need to do the same thing. For THOSE WHO KNOW the answer to this question, I would really appreciate knowing:

1) the terminal line to set max fan speed for each of the MP's 6 fans.

2) a list of RPM's converted to hex format for the command line (let us say 300 - 1000 going by 100's)

3) which smc version to run the term commands with?

Many people may be tempted to suggest different workarounds or the danger i might put my MP in - but I'm not here for that. Just here for help on the above question, thanks!!
 
Here are some numbers:

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

For more, there is a link to convert to HEX some post above...

I´ve got SMCfancontrol 2.4, and I´m experimenting with "MacBook Pro Fan Control" ...got it here http://www.derman.com/MacBook-Pro-Fan-Control

Folks, also read this thread to AUTORUN the SMC command at login to reduce MAX fan speed.... Creating the little program which runs the command line is easily done in the automator... its somewhere in the thread...
https://forums.macrumors.com/threads/468416/

So, my problem is that despite of all this programs and commands, the right fan is still doing more or less what he wants to do...

Can be related to putting an SSD in place of a HDD....
The temp. sensor gets disconnected on iMacs when replacing with SSD and likely on MBP too. I read that they short-cut some wires of the SATA power cable (2 & 7 or something like that) and that´s it....the fan behaves normally again

BUT haven´t tried it on my MBP yet... I don´t want to to damage those little cables. Let´s give it a try when I´m sure about which ones to short...

the last 24hrs I had disconnected the right fan totally, because the noise was too much...

MBP from early 2011

uf...sorry for my chaotic expression... spent already many hours in front of this...

good luck
 
Decode hex

60e in hex is 1550. 4 times that is 6200

3e8 is hex is 1000 decimal. 4 times that is 4000

So for 2500 you should use 2500/4=625, in hex is 0x271

So the setting would be /Applications/smcFanControl.app/Contents/Resources/smc -k F0Mx -w 2710
 
help !!

hello, im only new to this but i was wondering i downloaded the SMC FanControl and when i go on skype what speed/rpm would i set it to because it always overheats and it's really annoying thanks :)
 
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