Originally Posted by no2498
before you slow a fan down find whats making it run
type htop in a terminal it tells you how to install it
now run htop in a terminal see what is runnig
This is good advice. First find out if there is anything running the system hard, producing heat and calling for the fan.
As you eliminate this as the cause, I would like to know what the temps are. If sensors won't give it to you, an ugly way to get it is from the BIOS. Do a restart and go straight to Bios setup. There will be an area for seeing the hardware monitor/info or something like it. The sensor temps will be there. They aren't the live readings, but they will be pretty close.
When the computer is started from a cold start, does the fan run as fast and loud during the POST and BIOS part of the startup or does it only start when Ubuntu begins to load?