Normally, the fan speed is controlled from the "Task Manager". Instead, there may be a fan control program installed. For example, then link below:
There sometimes is a CPU Fan control icon in the Control panel depending on your computer brand/model.
Usually, it's controlled from within the BIOS which turns the fan on when there's heat build-up or working harder, etc. So be cautious...Slowing down the fan or reducing it's speed could potentially cause damage to the computer inards.
Hope this helps and let us know more..
where can i find my task manager to check on what i can do to decrease my fan from running on my brand new laptop.
i have xp