As with all Antec fans this one boast some quite impressive sound qualities being below 40db when in max use as well as good rates of air flow. So as expect the smartcool range offers good minimal noise and shifts air at an excellent rate. The smartcool fan is based on the same principle as their tricooling brothers and so has variable speeds to shift more air (and produce more noise at the same time).
As with all new antec fans it comes with the option of taking the power from the motherboard or directly from the PSU, for this range it is essential you take it from the motherbaord and you have a correctly compatible motherbaord! This is due to the fan getting the temperature from the motherbaord (hence the smart part) and if it can't it automatically assumes its far to hot and runs at a max speed constantly which kind of defeats the purpose of not getting the cheap one. However if you set this fan up correctly, and preferably have it as an exhaust fan so it can more significantly reduce the tempature on the motherboard it does run very quiet indeed as it only runs at the speed required :) so when you do start making you computer do a thousand and one things the fan gets a bit noiser but your system doesn't start to fry.
Also worthy of not remember if you get a bigger fan its more noisey but does shift more air, and one large fan is quieter than 2 small ones . . .
(If you don't have a spare compatible motherboard and want a smart fan get the smart Pro version as it has its own temperature gauge which you can place anywhere in the system, but of course this option is a bit more expensive)