BeQuiet SW2 PWM or 3 pin version

[Metro]

Hello

 

I have noticed there seems to be a noise difference compared to the PWM and 3 pin version, is this why there are not many reviews of the PWM version or do you think they want to save money.

 

Also is there a big noise difference as specs normally make things look better

 

Also what is better to use the S or L mount

 

Thanks

[dfsdfgfkjsefoiqzemnd]

PWM fans merely use a different method to determine fan speed.  Normal fans have their RPM controlled through voltage, PWM through the duration of pulses.

 

 

What fans you should use will usually be determined by what the motherboard or your fan controller supports.  A word of warning though : just because your motherboard has headers with 4 pins, doesn't mean it supports PWM.  I found that out after buying 8 PWM fans.  Granted, you can still use voltage control on PWM fans, but it's a waste of money.

 

As for the S and L mounts, S stands for "short", and in that position the rubber ring around the fan will be level with the mount.  If you mount it like that on a flat panel, it will touch it.  L stands for "long", and that side is indeed a mm or so longer, meaning that the rubber ring will be a mm off the panel. 

Each of my SW2 fans that uses the rubber mounts (11 out of the 14 I have in the PC and NAS combined) is on the L setting because it means the fan is mounted on just the 4 rubber corners, reducing the chance of resonance.  

[WoodenMarker]

Testing fans with varying voltage is easier than pwm.

The noise difference shouldn't be huge but I think pwm can be quieter being able to go lower speeds.