I haven't had any noticeable fan noise with my Slim, but my launch PS3, also behind a door (even with the back of the stand open), would kick the fan into high gear all of the time. If I had the door open, it always stayed quiet. I'm using open shelving these days for my components, and my Slim is always quiet. Using fans to get circulation on your PS3's space may be the way to go, but I'm definitely not the expert on putting that together.