Looking to get a different fan for the radiator before I get one.

Its a 3-pin header but a 2pin cable fan
 
Best is to mount a 4 pin static optimized fan on the radiator and connect the fan to the 4pin motherboard header

I've used just a single corsair sp120 high performance fan made for radiators and plugged it into a seperate fan controller and ran it at full blast and it wasn't loud at all and prob was overkill even. At first had push pull setup on it haha. Single push fan was fine in the end. Mid 40s on one card and upper 40s on the other on load.

Welcome to the Forums, Vustom
 
Some good advise above

I just did the same thing, i have a 120mm Noctua F series 4 pin fan connected to Rampage 4 pin fan connector on the motherboard. 
 
Its constantly running on about 1000+rpms and i can controll it from 1k rpm-2k rpm, but not any lower?
 
I want to run it at the lowest rpm setting when just cruiing the net or stuff like that.