what is this

[gman123]

what is that small fan underneth the cpu?

 

[jedimasterben]

That's the computer's North Bridge, most likely. I haven't seen one actively cooled (with a fan) in a long time.

 

[itotallybelieveyou]

IT's the north bridge. Usually you just get a chunk of metal there but you are lucky enough to have a fan on it

 

[PlugComputers]

A fan, thats oldschool. Ha but yes, that is the north bridge. Most now have fanless cooling as the others indicated, usually with some type of heat pipe.