The Lenovo X220 laptop fan has a life of it's own and it's pretty annoying if you try to work someplace quiet without headphones.
When doing nothing, the fan is way to loud. And worse, it has a tendency to rev up and down as shown on the video.
A BIOS update to version 1.16 is supposed to fix this - all I can say is: NO - THE PROBLEM IS STILL THERE.
Lenovo: You got to fix this!
Fellow laptop buyers: Find another laptop to buy!
Note: The model here is: Core i7, 2620M