I have found that there is only about 12-16mm of gap between the top of the fan and the top of my case, so its no wonder its going to full speed warp-9 takeoff velocity when doing anything cpu intensive. It sounds like its doing that tubine nose thing like when you restrict the airflow with your hand or something.
So I need one that either passes the air thru it horizontally, or one thats a lot shorter. Preferably a cross ways fan one since that will go straight into the exhaust fan...
But _QUIET_ = the case is an old low profile one I got a while back to put my firewall into before that idea fell down. I really need a lid on it before it goes in the loungeroom.