How big is the fan? My 12cm fan never goes over 900 RPM as well. The bigger the fan the slower it will spin, and therefore less noise, that's why I think bigger fans are better than smaller noisier fans that spin at a higher RPM.
Yeah, if your CPU is nice and cool, why would you want the fan to rev up? The slower the better because, the slower it goes the more silent it will be.
