Why are fans running at full speed?

Smirnoffkites

Smirnoffkites

Smirnoffkites

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Joined
5 Feb 2013
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28
Hi,

I've just finished my first PC build and have some questions on Fans, I hope you can help.

Just kitted out a Bitfenix Raider with my new kit (so pleased). The case comes with 3 pre-installed fans and a manual fan controller.
I've also fitted the CPU cooler that came with my CPU/MB bundle (a Megahalems - black series) this has 2 more fans either side of the cooler stack.

I was uncertain how to hook up the case fans (and controller) to the MB. No clear instructions. The 3 case fans appeared to be hooked up together and with a spare connector (a big 4 pin - a power connector??). I assumed this was for power so hooked it to a spare from my PSU. These fans do not hook to the MB!!!

Question 1: Did I do this correctly? I'm not sure the fans are being controlled by the manual switch (as the CPU fans are too noisey to hear any change in speed). But they are spinning.

Leading to Quations 2:

Why are the CPU cooler fans on 100% of the time at 100% speed? I thought they would come on when needed and controlled by the MB. These two fans are connected to the CPU and Opt connectors on the MB.

The MB is Asus P8z77-V

Thanks
 
Hi,

When you say "a big 4 pin" are you referring to a molex connector? if so then the fans connected to the molex will run at full speed all the time, you need to connect the fans to the fan controller via a the pwm connector/cable.
 
Hi,

I just googled "molex connector" (sorry, I don't know the names).

Yes, thats the one I connected to the PSU.

I think the PWM is the very small 4 pin plug from the fans themselves??

These were pre connected to a flat ribbon of 5 PWMs (3 used by the installed fans) I assumed the spare 2 were for additional fans if I ever needed them. This ribbon went up to the top of the case where the manual switch is located. Part of this ribbon also had the Molex.

I saw no other PWMs or any other spare connectors that could be used to go to the Mother Board. I assume that is where the fan controller is?

Please treat me as stupid, cos' I am!! :D

Should I disconnect the Molex?

Also, the CPU fans (connected direct to the motherboard by PWMs are also running at 100%. And I'm pretty sure I got those plugged in correctly (you can't fit PWMs the wrong way due to the plug shapes.

Please help

S
 
Smirnoffkites said:
Hi,

I just googled "molex connector" (sorry, I don't know the names).

Yes, thats the one I connected to the PSU.

I think the PWM is the very small 4 pin plug from the fans themselves??

These were pre connected to a flat ribbon of 5 PWMs (3 used by the installed fans) I assumed the spare 2 were for additional fans if I ever needed them. This ribbon went up to the top of the case where the manual switch is located. Part of this ribbon also had the Molex.

I saw no other PWMs or any other spare connectors that could be used to go to the Mother Board. I assume that is where the fan controller is?

Please treat me as stupid, cos' I am!! :D

Should I disconnect the Molex?

Also, the CPU fans (connected direct to the motherboard by PWMs are also running at 100%. And I'm pretty sure I got those plugged in correctly (you can't fit PWMs the wrong way due to the plug shapes.

Please help

S
Click to expand...

Yep, so you should connect the small 4 pin from the fans into the "flat ribbon" cables of the fan controller, the molex is indeed for power (the fan controller obviously needs power).

It sounds to me as if this is how you have it set up already, are you not able to manually adjust the fan speed of the 3 case fans?


The fans connected to your motherboard header may not be PWM fans, meaning they will run at full speed.
They're other alternatives, for example if your CPU is running really hot your mobo would run the fans at full speed to try and reduce the CPU temps or the fans are set in the BIOS to run at full speed.

Do you know the make and model of the fans on the heatsink?
 
Hi,
The case fans, I think, are set up correctly. I just can't tell if they are being controlled due to the noise of the CPU fans (easy to check)

The CPU fans are x2 120MM Zaward Golf III Fans. They came with the Meghelm cooler. Is this maybe a BIOS thing? Might it have been set like this? It was part of an OC'd bundle. i7 3.5 Oc's to 4.4 Mhz. I've asked the OC Bundle Helpdesk this question. As don't want to break the BIOS they have set.

Cheers
 
Smirnoffkites said:
Hi,
The case fans, I think, are set up correctly. I just can't tell if they are being controlled due to the noise of the CPU fans (easy to check)

The CPU fans are x2 120MM Zaward Golf III Fans. They came with the Meghelm cooler. Is this maybe a BIOS thing? Might it have been set like this? It was part of an OC'd bundle. i7 3.5 Oc's to 4.4 Mhz. I've asked the OC Bundle Helpdesk this question. As don't want to break the BIOS they have set.

Cheers
Click to expand...

Ah ok, well I think you have it set up correctly from what you've described :)

As for the CPU heatsink fans, well it depends on which Zaward Golf III fans were used,

These are not PWM: http://www.overclockers.co.uk/showproduct.php?prodid=FG-027-ZW EDIT: The fan speed in the description suggests it has a fixed fan speed, but it also says "The G3 Golf III Fan is designed to operate at multiple speeds and is especially effective when paired with a fan controller. " I would double check with OCUK.

But these are: http://www.overclockers.co.uk/showproduct.php?prodid=FG-058-ZW

If they are not PWM then they cannot be controlled via a fan controller or the motherboard, though you can buy 12V to 7V converters to reduce the current and so reduce the fan speed, alternatively you could replace the fans.
 
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