What's the best way to control liquid CPU cooler.

malbluff

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I am wanting to overclock (modestly) an i7-3770K, on an Asus P8z77-V PRO mobo. Am thinking of using Corsair H80 closed loop liquid cooler, but am unsure of the best means to control it. Corsair's "stock" method is to plug 3 pin connector to mobo's 4 pin CPU cooler header. They also provide a molex connector, to connect to PSU. (confess I'm not sure if that's a case of both, or either). Presumably, this way, radiator fan speed is contolled by coolant temp. There is a manual selector on unit, but understand that sets "max".

I have also seen a suggested alternative, where it's the radiator fans, themselves, that are wired directly to mobo CPU cooler header, presumably with pump wired directly from PSU. I take it, this way, fans are controlled, directly, by CPU conditions. Is this option "workable", and, if so, is it actually BETTER?

Please forgive what is probably a beginner's question, but, as it's my first self build, I am!

Many thanks.
 

nna2

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the H80 and H100 have built in fan controllers, i would set it on level 2 or 3, and it should keep itself cool, or plug it into the cpu fan plug and let the PWM controller handle it
 

diellur

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Apr 7, 2011
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The CPU fan connection on the H100 (and presumably other Corsair coolers) is only for RPM monitoring (of the pump, as it happens). The fans provided are not PWM capable, although the Corsair integrated fan controller provides the facility for PWM fans if you want to get some. I find the lowest fan setting is fine for the H100...my CPU idles at 28-31 deg C, depending upon ambient temps.

The power for the cooler pump and fan comes from the 12V molex...the integrated fan controller then allows you to vary the speed of the fan; no power comes into the cooler unit from the CPU header. You can set presets for fan speed, but it doesn't respond to CPU or coolant temp and adjust accordingly.

You can connect the fans directly to the CPU header and disconnect the cooler connection. RPM readings you'll get will now be for the fans, not the pump. If you have a splitter cable, you can connect multiple PWM fans to one CPU header...it'll be powered by a 12V molex and speed controlled according to the CPU temp. Just make sure you pick a PWM fan which has sufficient static pressure to work on the H100.
 

malbluff

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Many thanks. I think (I hope) I've got it.