Thanks for your comments johno. I forgot that the fan voltage doesn't rise above 5V until fairly heavy loading. After reading through this thread: http://www.silentpcreview.com/forums/viewtopic.php?t=36551&start=0&postdays=0&postorder=asc I think the Medium Speed Panaflo (FBA08A12M) might be the way...

I am planning on building a new computer using the Antec NSK3400 as the case and the ASUS M2A-VM HDMI as the motherboard. From what I've read, the case has an Antec SU380 PSU which was reviewed by SPCR. According to the review and from what I've read in various postings, the fan in this PSU is quite...