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I have installed Ubuntu 11.04 32bit on my Acer 7750g laptop, and very thing works like a charm except the fan which keeps running.

I researched on Google and found that perhaps I need to install lm-sensors. I did very thing according to the relative posts that I had googled. But the result of sensors-detect was only one driver `coretemp'. Then the result of sensors was:

Adapter: ISA adapter
Core 0:       +47.0°C  (high = +86.0°C, crit = +100.0°C)

Adapter: ISA adapter
Core 1:       +49.0°C  (high = +86.0°C, crit = +100.0°C)

Adapter: ISA adapter
Core 2:       +50.0°C  (high = +86.0°C, crit = +100.0°C)

Adapter: ISA adapter
Core 3:       +47.0°C  (high = +86.0°C, crit = +100.0°C)

And then I could not go any further.

Question 1: my CPU is intel i7 2630QM, but why only 4 cores are detected?

Question 2: why can't I find sensors of fans?

I have tried with lm-sensors 3.2.0 and 3.3.0. And I have read this , this.

share|improve this question

Your CPU only has 4 cores, but 8 hardware threads (2 per core).

Fan control under Linux is painful. You might like to watch a video of Matthew Garrett from the last LinuxConf AU to understand more of the problems faced by developers. He's the main guy for Linux laptop support from what I understand.


share|improve this answer
Very insightful, thanks for the link. – mikewhatever Jun 20 '11 at 21:54

In my, admittedly somewhat limited experience, many laptops either don't have fan sensors or they are not detected by lm-sensors. Regardless of the cause, the end result is - you can't control fan speeds.

share|improve this answer
but my laptop works perfectly with Windows 7, i.e., the fan is off when idle or light load. – wang.xueqiang Jun 19 '11 at 23:20
...but is there any way to control it's speed in W7? – mikewhatever Jun 19 '11 at 23:38
I mean windows can, Ubuntu cannot. – wang.xueqiang Jun 20 '11 at 12:34

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