...One thing I've noticed about homebuilt rigs is that they are occasionally louder than normal...
The last PC I built was substantially quieter than anything I could buy commercially. Indeed most of hte home-built quiet PCs now use they same tactics for quiet that I used 15 years ago.
At the time, the toughest component to get a quiet version for was the graphics card. Nearly all the ones I could find had one of those little whiny high-speed cooling fans on the card.