Advice: Replacing Dark Knight II Heat Sink Fan?

GolfPro24

Honorable
Feb 28, 2013
8
0
10,510
Hey,
I just installed a Xigmatek Dark Knight II in my build. It's cooling my Intel i5 3470 and idle/load temps are 30/50-55c . The fan, however, is a bit too loud for my liking in the mid to upper RPM Range so I am wondering a couple things here:
1. What Fans could/should I use to replace the fan?
2. Would it hurt to just install a static RPM Fan on the heat sink (decent CFM/lower RPM but low noise)?
3. Should I use a push/pull setup - how much would that improve cooling (example 1-5 degrees cooler) ?
4. For example, would this PWM fan be legit replacement?
http://www.newegg.com/Product/Product.aspx?Item=N82E16835553006

*I appreciate any legit advice, ideas, or suggestions. I enjoy trying to keep my rig quiet as possible**

My build:
Fractal Design Define R4
Asrock Z77m
Intel i5 3470
Gigabyte GTX 660oc
Seasonic 620w modular
WD 640 GB HDD