Hyper X Evo 212 dual fans

Solution
The EVO is a 4 pin connector but will connect to a 3 pin cpu fan board so you're fine there and im about 95 percent certain it has a PWM. The only thing is thats a case fan not a CPU Fan.
The fan that comes with the cooler is a PWM fan, so it is controlled by the motherboard and speeds up as the CPU gets hotter.
If you use these other fans, they will be fixed speed. This could be noisier than required when the CPU is at idle.
Other than that, if fitting two fans make sure they blow in the same direction.
 


Yes you can use whatever 120mm fan you want -you'll have to screw the bracket/clip onto it and snap it on.

Food for thought although. I have a evo 212 on a i7-5820k OC'd to 4.1Ghz.

At first I had the extra fan -in a push/pull config. I went to clean my case, and the push fan (blowing onto and through the heatsink) had a whole lot of dust build up behind it on the heatsink. I ended up leaving it off (so just one fan pulling air away from heatsink) and ran some benchmarks.

My idle and load temps dropped by at least 5C - 8C degrees. Obviously thinking the dust was the culprit I put the second fan back on, and ran the same benchmarks -and it barely made a difference. At most a single 1C better -and in fact the temps were higher in one benchmark.

Bottom line - I don't think the extra fan is worth it for the ~1C difference and now dust doesn't get caked up in the heatsink.

The stock fan that comes with it does me just fine -but if you want a nicer one/LED or whatever I recommend any fan made by Noctua:

http://www.newegg.com/Product/Product.aspx?Item=N82E16835608026

 


PWM fans always have at least 4 pins and has to be plugged into a 4 pin header on the board. Otherwise it just runs full speed DC all the time. Unless you have some adapters and/or fan controller.
 


These fans can't be speed controlled at all by the motherboard.
 
The noctua fans suggested above are very quiet, but just as expensive as your cooler and not LED fans.
Here is one that might fit what you want:
http://www.coolermaster.com/cooling/case-fan/xtraflo-120-blue/
It comes in blue or red LED and has PWM control.

As mentioned above too, the second fan will make very little difference to cooling.
 


Your original post about speed fan was a response to my post that the non-PWM fans he had linked may be noisier than required when the CPU is idle.
Speed fan doesn't help with this.

I've linked some alternative PWM fans with LED lighting:
http://www.coolermaster.com/cooling/case-fan/xtraflo-12...
It comes in blue or red LED and has PWM control.