Nexus Quiet Fan |120MM PWM Controlled Real Silent Case Fan | Ideal for a Quiet PC
I can't run slowly this fan.
In the BIOS is set to Automatic and Level 1.
Minimum speed = 1200 RPM.
Only with Speedfan i can lower about 800 RPM but don't work automatically the PWM controller.
Sorry for my bad english
No, those analog and digital chips are voltage regulators for the power used by the CPU. They are not used for fan speed control.
Fan speed control is always a compromise on mother boards, since there are no standards for fans about their start up speed and how much voltage is needed to start a fan spinning. All fans are different, some might start spinning at 5 volts or less, and others will need 7 volts before they will start spinning.
Mother board manufactures are worried that some fans will not start spinning if the fan speed control is set to the lowest speed. That will be a big problem for fans on a CPU cooler, the CPU could over heat and owners will blame the mother board manufacture.
So mother board manufactures will set the lowest fan speed setting for the CPU fan high enough for 99% or more of the fans used to start spinning. Your Nexus fan has a very low starting voltage, lower than most other fans, so even at the lowest CPU fan speed setting, it will spin faster than most other fans, 1200 RPM.
Some ASRock Z77 boards had a setting added to the BIOS, for the CPU fan speed setting. It let you adjust the starting CPU fan speed/voltage much lower than the other settings. I don't know if your board has that setting, I think it was called Custom. What BIOS version are you using?
I bought the following fan which after trying quite a few fans, I found this suit my needs:
Akasa Thermal Solution
In order to have the PWM working via the BIOS, the fan will need to have a 4-pin connector & will need to connect to a 4-pin header on the motherboard. On mine that was the Chassis Fan Connector 1 "CHA_FAN1".
Chassis Fan Connector 2 "CHA_FAN2" on mine is only a 3-pin header & doesn't support PWM Fan Speed Control. I'm not sure why ASRock didn't provide more PWM Fan Connectors. Obviously, my CPU's Fan is connected to a PWM header as I have that on automatic PWM control.
When I set my fan to Level 1 in the BIOS, my fan runs at about 600rpm (can't hear it) & at Level 9 it's running at almost 2000rpm (very noisy). Perhaps if you want better control over the fan speed, then maybe try a different fan. There are some which have variable fan speed control & others which have a 2 or 3 position fan speed switch but that means you adjust it manually & not automatically via the BIOS PWM function.
As my motherboard doesn't have a second PWM header for a case fan, that's what I'm going to have to do in order to have an adjustable exhaust fan. I've also seen a Fan PWM splitter cable which apparently will drive 2 PWM Fans from 1 header but I have no idea how effective they are or even if they work!
I hope that helps.
Last edited by RickJP909; 11-09-2013 at 08:39 AM.
Your Nexus 120mm PWM fan (I have one, not using it now) must have the lowest starting voltage of almost any other fan! Is there a temperature setting when it is set to Custom, I don't remember. But you would have tried that too, right?!
I don't think there is anything else you can do, besides using a fan speed reducer like those that come with Noctua fans. But that would also limit your top speed to below 2000 RPM, which may not be good for your CPU temperatures.
I've seen in the web many similar problem:
I tried all possible combinations in both the BIOS and the connectors:
Then I measured the voltages with the tester: i note in each connector to a minimum 6.1/6.2 Volt.
Same thing with AXTU.
At the end if I want to turn the fan to 500 RPM should i install Speedfan (without PWM control).
The fan complies with the characteristics given by the manufacturer, the controller ASRock seems not.
Depends on the manufacturer as they thought to bring together the period and the duty cycle of the MoBo controller.
Yes, I agree with you and that's very interesting but did you note my previous post? I may be a new member on this forum but I'm a qualified engineer with many years experience.
If you can't lower the speed of the fan in the BIOS or using the controls in the AXTU utility, then you will need to seek a fan from another supplier. As you've measured the voltages on the pins and noted what they are and it appears that there maybe some discrepancies with what should be expected compared to what the controller that ASRock is using, have you tried reporting this to ASRock support? Unless your board is faulty or slightly out of tolerance, this could be expected behaviour and within the technical variances expected, in which case there is little you can do using your current motherboard.
However, as I stated above, I provided a link with a quiet fan which I use from Akasa and this works perfectly therefore I don't believe this is a direct issue with ASRock boards otherwise my fan wouldn't work as expected.
Perhaps the tolerances of the Nexus fan are too strict whereas the Akasa is more flexible?
Anyway, the issue still remains that the Nexus doesn't work as expected so it is therefore cheaper to change the fan to one which does work rather than change a motherboard to work with your fan.
I also compared the specifications of the Nexus fan with the Akasa Viper and to my eyes, the Viper out performs the Nexus, even though it looks very impressive, the Viper wins for me and I can confirm it works really well!
Hope that helps.
Last edited by RickJP909; 11-09-2013 at 09:16 PM.
Yes, clear.Originally Posted by RickJP909
No doubt it :-)Originally Posted by RickJP909
Maybe so.Originally Posted by RickJP909
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