A new feature of a lot of computer case fans is PWM, meaning Pulse-Width modulation. Instead of varying the voltage to a fan, it pulses. Imagine flipping a light switch on for 10 seconds, then off for 10 seconds, and then repeating. Well, PWM is like that, except much faster. To vary the speed of the fan, instead of 10/10, you might do 15 seconds of light with 5 seconds of darkness. What’s the reason for PWM? Well, with the old-style of varying speed or power, a variable resistor is used. This resistor makes the fan move slower by basically absorbing the power difference and heating up. Heat is the killer of electronics and is an enormous power waster.
Scythe’s SlipStream fan has 9 blades!!
Scythe has released a line of fans called the SlipStream. They offer both PWM-only fans as well as PWM-variable speed fans using a combination of PWM and variable resistors in order to give you all the control. When you need silence, turn the fan down. When you need ultimate cooling, turn it up. I got a pair of 120mm SlipStream fans to take a look at with only the PWM function. I never have to limit my volume, so I’ll let the electronics do it for me.
Scythe’s new PWM fans really win! They provide excellent cooling with a low volume penalty. With more and thinner fan blades than most of the competition, Scythe’s geometry allows it to move a lot of air.
Scythe claims to move up to 74.25 CFM of air with it’s 120mm PWM fan at only 26.5 dB. Of course, if the fan cold it will run at a slower speed, moving less air– all the way down to 0 RPM. Immediately after playing around with a couple of Antec and Masscool fans, it is obvious that the Scythe fan moves more air and is only slightly louder. With the case back together there is no obvious difference in loudness.
Overall, these fans are an excellent general purpose fan. Without having to worry about volume levels and still knowing they will cool your components, these fans are perfect for any system builder. The fans are rated at 30,000 hours MTBF, so approximately 4 years of being on continuously.
It comes equipped with a 3/4pin to Molex converter and 4 fan screws too.
[Scythe SlipStream 120mm PWM Fan] – $10.95