Can't choose the right PWM fans

[ytzelf]

Hello all, first post, I hope I'm doing everything like it should be done...

I am gonna change my cpu cooler from Noctua NH-U12P SE2 to Corsair H70 pre-made watercooling. The thing is, I already own 2 Arctic cooling f12 PWM fans. My i7 920 is OCed at 3.7ghz, load at abt 70C, and these are spinning between 1200 and 1300 RPM (when rated at 300-1300).. Not exactly deserving the "PWM" name : they are too loud at 1200 and not efficient enough at 1300. I guess they spin too fast at idle because the Noctua ain't cooling enough, hence the change..

I would like to change the fan, too, getting some with a wider spinning range. It HAS to be PWM. For now, I've spotted:

• NoiseBlocker BlackSilent XLP
• NoiseBlocker Multiframe MF12P
• Akasa Apache

Those spin between 1000-2000RPM (roughly). I'm personnally considering the MF12P. I already have NB fans and these are OK. Don't have any info on the Apache though.

The goal of all these change would be to get a system less noisy at idle (cause of better cooler) and more efficient at load (cause of higher max RPM fans)..

So I'm asking you guys some advice about other CPU cooler / pwm fans I may have missed. I am practically sure abt the H70 though, so let's talk fans (I don't know much abt 38mm thickness fans, son help on these would be appreciated) =). Please don't advice non PWM fans or rheobus, I don't want these ugly thingies on my comp face.

Thanks in advance !