I'm not a silent PC guru, but thanks to this site and forum I carefully cherry picked my cpu cooler, fans, HD, GPU, etc. I wanted a small case so I got a Silverstone GD05, coming from a standard noisy PC I was quite satisfied by the very low noise of my new rig but after a while I started to notice it.
I read that the case doesn't impact that much on the overall noise but I ordered an Antec P183 anyway (I had a P180 once and it was great). Well, of course they are 2 completely different cases, but noise is definitely reduced by a good amount. The PC went from being silent to being (almost) mute.
The GD05 was vibrating too much I think, if I put a hand on the top of the case I could feel it vibrating, while the P183 is steady like a rock. In a couple of weeks I'm sure I'll start noticing the noise of this new setup as well... you can always make it more silent
![Smile :)](./images/smilies/icon_smile.gif)