Most helpful positive review
In summary: good for the price, a little noisy, don't install horizontally blowing down.
on 18 February 2014
These are very cheap fans, but they're quite noisy. When I first bought them another review said they were a bit noisy and I was hoping they just spin too fast, but that's not it. There's a noticeable bearing noise, especially when it's held horizontally with the blades pointing up, and the fan blades passing over the motor's struts creates a distinct hum. I then ran the fan at 5 volts instead of the 12 it's rated at, and now that hum has mostly gone away. The bearing noise is still there though. They still move enough air to be used as a case fan at 5V, provided your system isn't too high-end. Lastly, fan is pictured with 4 screws. You'd probably need to know those aren't included.