Acoustic Foam and its effectiveness with case fans

[WeaponX]

I want to put a 120mm panflo fan in the side of my case below the CPU and on top of my case. But I also want to use acoustic foam to make my computer less noisy. How effective will the acoustic foam still be? I'll put one sheet on my case door and one behind my mobo(on the wall). I will have to cut a hole in the foam for the 120 mm fan too. Will the acoustic foam still make a difference?

 

[IFMU]

By my understanding of how the foam basiclly works and what-not, it should work fine. There will be some noise it wont be able to deaden, but the for the rest it should work great. So overall it will kill off most of the noise your trying to get rid of.

 

[WeaponX]

Weeeeeeeee Thanx