I disabled internal wifi (intel 2100 b).
Downclocked ATI 7500 to 200MHz.
All this to minimize disturbing heat sources.
Then I started som CPU intensive programs.
The fan kicks in when temp reaches 47 deg. Celsius.
The fan stops when temp reaches 42 deg. Celsius.
I tried it many times, got consistent readings.
All meassured with mobile meter and centrino hardware control 1.7.
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So what triggers the fan to run constantly even when the computer is just idling at ~36 deg. Celsius (600MHz, wifi enabled, ATI at stock speed)?
I tried to cool the components (one by one) that looked suspicious until I found the right one. I have marked the [censored] in the pictures...
"AM7" is printed on top of it...
If the cpu temp is below 42 deg. and the fan is running, I can make the fan stop by blowing my breath on the sucker. It never fails...
Seems like it just slightly overheating/oversensing.
Now my plan is to mount som kind of pipe that can direct cold air from the fan to the space that is too hot.
Do you experts have any other ideas?

