Fan connectors on P180 and P5B

[wgoldfarb]

I am doing my first build, and I have what seems like a noob question.

The fans that come with the P180 Case have what appear to be standard 4 pin connectors, but it looks like only 2 of the pins are actually used (ground and power).

The chassis fan conectors on the P5B MoBo have THREE pins, labelled Ground, power, and "rotation". I assume Rotation is the way that the fan would tell the Mobo its rotation speed. the Antec case fans seem to lack this third wire. Am I correct?

What is the correct way to connect the 4 pin connector from the fan onto the 3 pin conector on the Mobo? From the diagrams on the mobo manual it would seem that if I simply plug the 4 pin conenctor onto the 3 pin connector to line up the power and ground pins on both connectors, the ground and power pins would be reversed. I assume this can be easily corrected by fliiping the fan over, but I don't know if there are any other consequences.

If there is anyone with this same Mobo/case combination, could you please let me know how you connected your fans to the MoBo?

 

[WoodButcher]

Have you looked at the size of the mobo connectors vs the fan connections? I'm fairly certain your case fans have molex plug to connect to your PSU. The only other 4 pin is the PWM which is generally associated with the CPU heat sink.

 

[tylerdustin2008]

You can get one of these.

http://www.performance-pcs.com/catalog/...main_page=product_info&products_id=608

Or just hook the fan up to the PSU.

 

[wgoldfarb]

Woodbutcher/Tylerdustin,

Thanks. I hadn't actually looked at the MoBo's connectors, I was just looking at the manual. I just looked at the MoBo itself and the connectors are indeed MUCH smaller than the molex connectors on the fans. So, I can plug the fans directly into the PSU, or get the adapters suggested by Tylerdustin and hook them up to the MoBo's controller.

So, the next question, which is better? The case fans have a switch which allows me to select between 3 speeds. In theory, according to the manual, the low speed is very silent and should be enough for most configurations (my PSU is not here yet so I cannot try this yet). I could hook both 120 mm fans to the PSU, set them all to low, and leave them there. The alternative is to connect them to the MoBo and allow Asus' Q-fan2 utility to control the fans, but for that to work I believe I need to set the fans to high (or the voltage supplied by Q-fan2 may not be enough to start the fans).

I guess what I an trying to understand is this: Is it worth getting the adapters? How much difference will it make in terms of the system's noise and/or cooling?

Thanks again,

 

[tylerdustin2008]

The only advantage for using the mobo connectors is having the RPM sensor, not really needed. How often do you care about the RPM? I would hook them straight into the PSU and leave them on high, they are not that loud. And according to your sig it seems like you have a nice setup that will get hot, so high would be the best, unless you are godly at cable management and can then leave them on low.

Tyler

 

[wgoldfarb]

tylerdustin,

Isn't there an advantage of allowing the mobo to adjust fan speeds? That way they could run at low most of the time, increasing the speed only if/when the mobo senses a rise in temps. Wouldn't it make for a quieter system, without sacrifing much in terms of cooling?

Still, for now, since I don't have the adapters (and don't want to wait!) I will follow your suggestion and hook them up to the PSU -- I will play around and see how noisy/cool the system is at different fan speeds.

Thanks for the info!

 

[WoodButcher]

Your fans do not have the rpm sensor wire so the adaptor to the mobo is a moot point.