[ltp] repeatedly turning on and off bad for fan?

[Paul RIVIER]

Hello Jiang

>Hi All:
>I installed the script by Erik Groeneveld to turn the fan of my T43 on 
>and off between 55 and 65C. My concern is: given that I read in windows
>the fan never turns off
>(http://www.notebookreview.com/default.asp?newsID=2285)
>I wonder whether the IBM design the fan to be always on and therefore 
>turning it on and off frequently(mine does it in about 10 minutes 
>cycles) is bad for fan, mechanically because it is designed to be 
>constantly on at an approximately constant speed(mine 4000rpm)?
>
>  
>
I wrote a script too, and there is actually no way to control the fan 
*speed* on T4x series.
I would prefer too to anticipate overheating by monitoring CPU/GPU usage 
and so  speed up / down the fan ... but ibm-acpi does not permit it yet. 
I do not have windows to check wether the fan stops or not.
I know that a lot of laptops (including sony vaios) have also an 
hysterysis based fan control, I mean it starts when hot, stops when cool.

>I'm new to the list. I have a thinkpad T43(2668W12) running ubuntu 
>hoary with 2.6.12-4 kernel with various patches.
>
>Also as a tip I took from Paul Rivier that's a real revelation: the 
>DynamicClocks feature of xorg ati driver got turned off after returning 
>from suspend because of vbetool. Now I removed all vbetool reference in 
>my acpi scripts(I use mesa radeon driver and no framebuffer console so 
>it is not needed anyway) and now my GPU is as cool as before after 
>resume. That's why I decided to start using fan control daemon because 
>it is cool enough all the time to do so. See:
>
>http://mailman.linux-thinkpad.org/pipermail/linux-thinkpad/2005-July/027539.html
>
>Thanks a lot Paul for figuring this out!
>  
>
You are welcome. That drove me mad for a couple before I found the 
solution :)

>Did anyone get hard drive park working for hdaps in T43? I got the 
>latest 20050825-02 version. After installing  the modules I don't seem 
>to get the /dev/hdaps device as said in README. The various readings in 
>/sys seems working, just backwor
>  
>
hdaps or parking ? I did never try to read hdaps sensor, but I parked 
successfully my drive last month (T42-60GB)

paul

>Jiang
>  
>