My standard for quietness is the Scythe SlipStream 800rpm - if any fan is as quiet as that fan when new and does approx that cfm I'll use it! Unfortunately heard not so good things about longevity of those - a bit hesitant for now to order one of them...
- choices would be between S-Flex D 800rpm / Gentle Typhoon 1150rpm / GT 1450rpm / noiseblocker blacksilentpro PL-2 (only model available here, will have to mod voltage as it's not quiet at 12V)
- could anyone can tell me how long their fans have lasted? their noise levels in relation to a SS 800rpm? do they get much noisier as time goes by?
- or do you have personal experience to the contrary about slipstreams' longevity?
The Slipstreams last a long time, easily ten thousand hours for me and going strong. The only fans I really like are the Nexus 120 and Slipstream 800. I bought several low-speed S-Flex fans, and they all exhibited a variable pitch whine. Noctuas can do that, too. The Gentle Typhoon 1450 I recently bought is hands down the worst fan I've ever had. It's bad for vibration, it buzzes, and it's got a loud variable pitch whine. It's horrible at all speeds. I've probably spent $200 auditioning fans over the years, and the only ones that have been consistently good for me are the Nexus and SlipStream 800.
As for CPU fans, I have Hyper 212 Plus HSFs in both my PCs. The stock CoolerMaster fan is pure crap. On my E6600 system, I strapped a Slipstream 800 on it and called it a day. On my main system, an i5 750, I tried a Gelid PWM fan and Apache S-FLOW, and while they improved on the stock Cooler Master fan, they were still loud, idling around 750 RPM at 20%, which is as low as my mobo goes. I gave the Slipstream PWM fan a try, and it idles around 320(!) RPM. Under load, it never rises above 600 RPM. My case fans are a Nexus at 680 RPM and Slipstream at 470 RPM in the upper and lower chambers of my Acoustipack'd P182, and I also have 3 WD Green Drives in the lower chamber. The video card is a passive 9600GT, and PSU is Seasonic X650. Replacing the CPU fan was the best thing I've done for this system noise-wise in a long time. All I can say is that the CoolerMaster, Gelid, and Apache PWM fans idle higher than is necessary to cool my non-overclocked system at full load, and they are not silent at idle in my system. The Slipstream PWM is silent at full load.