One of my favorite, if expensive, case designs from the past couple of years has been Thermaltake's Bach series. One of the design points of the case is two 60mm fans placed to exhaust air from the central processing unit. One of my problems with the retail Bach's is that factory included fans really aren't that good. Of the 3 units I have personally, and the 4 that I've built for clients, the original fans in all but one failed over within 6 to 8 months. Well, finally the fans in the last unit left started having problems so I went looking for a new set of fans.
I settled on Evercool's LD6025B-EC2 60mm fan, which was about $5 from Newegg. The tech specs of the fan were right in line with what I was looking for. It's claimed 2300±10% RPM speed, 31.62 CFM air flow, and 26 dBA noise sounded too good to be true. It was.
Yes, the Evercool LD6025B-EC2 can actually move 31.62 cubic feet per minute. It does not do it at 26 dBA. Two of these in my Bach case sounded like dueling Banshee's each having a crisis. My 6600 GT's from XFX made less noise than the Evercool fan.
Rather, I found something interesting on the package that was actually delivered. While Evercool's site, and Newegg, claim that the fan moves at 2300±10% RPM...
The packing claims that the fan runs at 4500rpm... which sounded a lot more like what the fan was doing.
In order to tone the noise down, I wound up putting the fans on some Zalman Fan Mate 2 controllers. My plan is to pick up a rear-slot fan speed controller and a 3pin wire splitter later so that I can control the fan speed without having to open my case up, and with using one in-expensive controller.