Laptop cooling fan stops suddenly

I'm having this problem for a long time. The cooling solution (single fan for CPU and GPU) on my LG 590 (5700) laptop, suddenly stops to work and don't start again causing overheat and consequential system shutdown to prevent damage.

How can I solve this?

[I'm using Ubuntu 12.10 but the laptop was originally designed to run Windows.]

Thanks for your replies.

• The fan works normal on Windows. It doesn't stop cooling even under heavy load such as games or full hd videos. As the processing temperature increases, the rotation rises too. In Ubuntu it happens in reverse; when under heavy load it just stops spinning.

• I always use the latest stable driver version of graphics card.

• I have fancontrol installed because of this post: "How to control fan speed?". Even tried to follow the tutorial of the final answer but got stuck after "sudo pwmconfig", where it shows this: "There are no pwm-capable sensor modules installed".

It worth mentioning that the reporter has also fired a bug for this: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1125052

So it will be also tracked there...