I've been on the hunt for small, quiet fans for use in a <!-- BBCode Start --><A HREF="http://www.msi.com.tw/program/products/slim_pc/slm/pro_slm_detail.php?UID=66&MODEL=MS-6215" TARGET="_blank">Microstar MS-6215 Slim PC</A><!-- BBCode End -->. The two real noisemakers in this system are the 60x10mm CPU fan (a <!-- BBCode Start --><A HREF="http://www.deltaww.com/products/dcfans/pdf/EFB606010.pdf" TARGET="_blank">Delta EFB0612HA</A><!-- BBCode End -->) and the 40x10mm PSU fan (an <!-- BBCode Start --><A HREF="http://www.addausa.com/specifications/up-40.pdf" TARGET="_blank">Adda AD0412MB-G70</A><!-- BBCode End -->).
<BR>Here are fans I've listened to as potential replacements for these two fans.
<BR>Sunon KD1206PFB1-8 (60x10mm)
<BR>Sunon KD1206PFB2-8 (60x10mm)
<BR>Aavid 1450223 (50mm, came with Via C3 CPU)
<BR>Coolermaster Unspecified Model # (60x10mm, silver label on frame hub, silver and blue Coolermaster label (like Lysis))
<BR>Lysis P2CS2HC-F1 (60x10mm)
<BR>Sunon KD1206PHB1 (60x15)
<BR>Sunon KD1204PFB2-8 (40x10)
<BR>Power Logic PL40S12M (40x10)
<BR>YS Tech FD1204105S-1N (40x10)
<BR>Fonsan DFB0412LL (40x10)
<BR>Sunon KD1204PFS3 (40x10)
<BR>By far, the two quietest are the Lysis (about which I could find no infomation on the web, except that fans branded Lysis are used some older HSFs sold by <!-- BBCode Start --><A HREF="http://www.coolerstar.com/lysis.html" TARGET="_blank">coolerstar.com</A><!-- BBCode End -->)and the Sunon KD1204PFS3. I acquired the Lysis (which is incredibly quiet-- it spins so slow that it's reported as 0 RPM) at a computer show in a surplus bin, and the Sunon was pulled (I think) out of a DigitalDoc5. The two of them combined make for a much quieter system than the stock parts, but still much louder than one can accomplish in a full-size PC.
<BR>While a few computer websites do sell small fans, they are typically the highest RPM models (for example Sunon B1s or S1s instead of B3s or S3s, or Delta HAs instead of LAs). The only exception was <!-- BBCode auto-link start --><a href="http://www.silentmods.com" target="_blank">www.silentmods.com</a><!-- BBCode auto-link end -->, which apparently <!-- BBCode Start --><A HREF="http://www.silentmods.com/" TARGET="_blank">no longer exists</A><!-- BBCode End -->.
<BR>Some electronics websites do sell these and other low-RPM small fans, but typically for outrageous prices ($15 for a 40mm fan? At least when you pay $20 for an 80mm Papst it has some presence), or only in bulk lots.
<BR>So far, it seems to me that my best chances are to hope that vendors at computer shows are getting rid of some surplus, and hope I chance upon something like the Lysis fans again. (In my system right now, I'm running a Lysis on the CPU, and another secured externally over the vent port where the 40mm PSU fan is supposed to go.)
<BR>If anyone has any information about where I might find some more small, quiet fans, please let me know.