Well its loud enough to let you know its there, but the noise is not excessively loud in my opinion. Rather than look at the noise which is often discussed as being a negative thing, I view it in a positive aspect as I will know if it ever stops..
Loud Fans save CPU's.... A great quote by Mr B which says it all
Well, it's not so loud (well, it is) as it whines like a little girl who just wet the bed. High pitched and annoying. I managed to sleep in the same room with it, though I did have several nightmares about my computers attacking me.
i took my fop 38 fan off and rigged up a a 90mm case flan sucking from a duct hooked to the heatsink. then added another fan in the top. it cools the same but is actually quieter now. *shrug* fop38 is good, but LOUD