PC Power & Cooling also makes
these, and I can vouch for their silence. I own one, and I can barely hear it even if I put my ear right up to it. It doesn't move a TON of air, but neither do Panaflo L1As and they do their job quite well.
These fans also have a five-year warranty. And they're ball bearing fans, which are generally recognized as having longer effective lifespans than sleeve-bearing fans. The fan I linked to above is also available with a 4-pin molex connector if you wanna power it directly via the PSU. I think it also has a temp sensor in it that ramps it up or down depending on how hot things get. Mine, that I bought over a year ago, does.
Don't mean to sound like a fanboy here; they're just nice nice fans. I've been reading some posts on this forum about Delta fans being pretty good too, and Adda as well. Panaflos are now being made in China under the NMB-MAT moniker, and there's been some question as to whether or not they're the same as they used to be. Jury's still out in my mind, as I've read several negative comments about the new ones. Papst also has a reputation for making very high quality fans, but they used to be made in Germany and are now being made in Hungary, and I don't know if there are any quality issues with them or not. Haven't heard or read anything about it at all.
Incidentally, the sleeve-bearing 80mm fans that came with my Cooler Master WaveMaster case are very quiet as well. Can't complain about them at all.
Hope this helps. Good luck.
