Ok because no one else is willing to say anything. lm-sensors is the package in ubuntu that will help with your quest the first thing to find out is whether lm-sensors detects your gpu temperature sensor as this is what will probably control the speed of the GPU cooler fan. To test whether your gpu temp is detected you will need to paste this command in a terminal first.
This will go through a sensor detection script it will then output a section of code to add to your modules file which will load additional modules specific for your system. It should look some thing like this.
# I2C adapter drivers
# I2C chip drivers
you will need to add this to etc/modules/ you can open it with
gksudo gedit /etc/modules
I suggest you take a look at the howto by DeMus on the Ubuntu forums as it goes in to much more detail you can check it here.
after you have got the output of the sensors command paste it at paste.ubuntu.com and add the link to original question and I will be able to see if you are going to be able to continue to the next level Quest!