Fans ignoring curve

[Blofeld2k]

check this image out. I have set all 4 extra fans to 300RPM up to 60C then it increases to 2000RPM between 60-n.

 

It still run the temps the way it wants though (image).

 

Any ideas?

 

[DevBiker]

What kind of fans are they?

 

It's quite possible that they cannot go that slow and what you are seeing is the slowest possible speed for the fan.

[DevBiker]

Also ... your fan curve is wildly inappropriate for the H110 temp. Your coolant should max out around 40C (give or take depending on environment). If your coolant EVER gets to 60C, you've got major issues with the cooler that would require RMA. So you'll want to adjust your fan curve accordingly.

[Blofeld2k]

The fans are:

Noctua NF-A14 industrialPPC-2000 PWM 140mm

Corsair Air Series AF140 Quiet 140mm

 

and they can go 0 RPM so what I don't get is why they can't go 1-299?

 

not sure I get what you mean by my curve, It runs at around 40C so I don´t see the point in making it start spinning >41C?

[DevBiker]

The fans are:

Noctua NF-A14 industrialPPC-2000 PWM 140mm

Corsair Air Series AF140 Quiet 140mm

 

and they can go 0 RPM so what I don't get is why they can't go 1-299?

 

not sure I get what you mean by my curve, It runs at around 40C so I don´t see the point in making it start spinning >41C?

 

Your H110i GT liquid coolant runs at 40C? :eek:

 

And - here's the deal. Most PWM fans will run at a minimum speed when they have any kind of power signal, even if the PWM signal is at zero. For them to completely stop, the power needs to be stopped. And there's a minimum speed that the fan can go to overcome the initial friction of just getting started or it stalls out.

 

Think about your car engine. It can be at 0 RPM. It idles around ... say ... 900 RPM. What happens if it goes down to, say, 750 RPM? Would you expect it to be able to do that?

[c-attack]

Noctua Industrial A14i 2000 rpm PWM fans have a minimum of 500 rpm, although with some controllers I can get it closer to 400. Regardless, that is pretty low for a fan with a 2000 rpm maximum and the word "industrial" in its product name. As suggested above, the Commander Pro is able to achieve the zero rpm state by simply cutting off the signal entirely, not ramping it down from 500-0. It is likely the start-up sequence may make them jump higher than 500 rpm initially. Most fans cannot start-up at their minimum. Additionally, I am not sure what there is to gain by trying to run 300 vs 400 rpm. At those speeds, blade noise is irrelevant and what you are likely to hear is the motor. It won't sound any different at 200-600 rpm. Full OFF certainly does cut the motor noise, but if you get a fan blast to resume, it may not be worthwhile compared to a slow and silent pace, which leads to the next issue.

 

40C idle coolant temperature. My hunch is you have reached this level because you are keeping the fans in an off state the majority of the time. While this can work for light desktop work and browsing, know you are likely applying a +10-15C penalty to the CPU with what appears to be a 24-25C room/case temp. Again, this is mostly irrelevant at 40C when the voltage is stepped down, but if you were to initiate any kind of 100% activity, that 40C coolant temp is now your base minimum CPU temp and the spike in activity is going to take you up to 70-90C, depending on your Vcore and related settings. This is your decision to make, but understand how the coolant raises the minimum CPU temperature. You can't flip the fans on under load and expect it to knock 10C off the coolant. Even at idle it would take 5 minutes+ to with higher fans speeds to shed the heat. If you are running the fans at 500-600 rpm and your coolant temp is 40C, we need to find out why. That suggests a problem.

 

I recognize the 464 rpm fans as the A14i. Which ones are the AF140? The 1000 rpm+? Are those fans properly set to DC in the C-Pro settings? That is maximum, suggesting they may be in PWM mode.