The PSU is the loudest part of the system
Going to an external power brick is an option for lower voltage systems but I don’t think I’m quite at that lowest of levels yet.
76w Prime95 Torture Test
At 76w you could use the following 120w fanless power brick.
a href="http://www.mini-itx.com/store/?c=10#p1806"http://www.mini-itx.com/store/?c=10#p1806/a