[SOLVED] Anyone recommend me the best setting for the fans?

WrongRookie

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Oct 23, 2020
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I have a fan hub but for some reason, if I set my motherboard to quiet, it acts as though one fan isn't there. But when I set it to other settings, it acts as all the fans are there somehow atleast from the BIOS menu

Anyways the point is that I would like a fixed setting so that the front fans and the back would rotate as they should when the CPU operates normally or when it gets under load. Can you suggest me the right settings for the front and rear fans?

View: https://imgur.com/yzbDwIz

View: https://imgur.com/Yxn8oxy

View: https://imgur.com/iJqfYx2


I've given the CPU fan for reference. Right now I've set it as quiet. The reason I'm concerned is that the front and rear fans tend to fluctuate their speed when the BIOS is set to quiet for the fan control.

Mother board is Supermicro C7H270-CG-ML

These are the fans that I have
Deepcool RF120FS
Corsair ML140 Pro X 2
And the CPU is Intel i7-7700
 
Solution
That bios is seriously confusing things. Lol. From the way it looks for Sys_fan1, temperature 1 is the low point and temperature 2 is the high. The pwm1 and pwm2 settings should be the % setting. So according to that when the PCH (don't know why they chose that since it's the big chip with a heatsink on the upper right side) reaches 20°C the fan should be at 20% and if the temp reaches 100°C it'll be at 100%.

Temp/pwm 3 + 4 will be additional set points, so if usable you could set 1 as 20% at 20°, 2 as 50% at 30°, 3 as 60% at 40° and 4 as 100% at 100° etc. 4 setpoints representing the fan curve, as long as the values get larger in progression.

Normally motherboards will use either analog or pwm so not sure if the supermicro is pwm...
I have a fan hub but for some reason, if I set my motherboard to quiet, it acts as though one fan isn't there. But when I set it to other settings, it acts as all the fans are there somehow atleast from the BIOS menu

Anyways the point is that I would like a fixed setting so that the front fans and the back would rotate as they should when the CPU operates normally or when it gets under load. Can you suggest me the right settings for the front and rear fans?

View: https://imgur.com/yzbDwIz

View: https://imgur.com/Yxn8oxy

View: https://imgur.com/iJqfYx2


I've given the CPU fan for reference. Right now I've set it as quiet. The reason I'm concerned is that the front and rear fans tend to fluctuate their speed when the BIOS is set to quiet for the fan control.

Mother board is Supermicro C7H270-CG-ML

These are the fans that I have
Deepcool RF120FS
Corsair ML140 Pro X 2
And the CPU is Intel i7-7700
You have 2 different fans, are they tied together ? Are they both 3 or 4 pin ? Are they set in BIOS to Voltage or PWM control ?
For case fans it's not good to be tied to CPU temps or they might be to "jumpy", better to tie them to MB temperature.
If BIOS lets you adjust speed curves, It's best to set straight line from temps at idle to few degrees before highest allowed temps.
 
You have 2 different fans, are they tied together ? Are they both 3 or 4 pin ? Are they set in BIOS to Voltage or PWM control ?
For case fans it's not good to be tied to CPU temps or they might be to "jumpy", better to tie them to MB temperature.
If BIOS lets you adjust speed curves, It's best to set straight line from temps at idle to few degrees before highest allowed temps.

Rear is a three pin while the front are two 120mm fans.

So the case fans have to be in PCH right? But then what would be the best temp for that? All I know us that the rear is connected to the motherboard while the two in the front are connected to a fan hub.

How to tell if they are in PVM control?
 
Rear is a three pin while the front are two 120mm fans.

So the case fans have to be in PCH right? But then what would be the best temp for that? All I know us that the rear is connected to the motherboard while the two in the front are connected to a fan hub.

How to tell if they are in PVM control?
You should see that setting in BIOS. 3pin - Voltage control, 4pin (even thru hub) - PWM.
 
You should see that setting in BIOS. 3pin - Voltage control, 4pin (even thru hub) - PWM.

I searched in the BIOS but this is what I could find

View: https://imgur.com/BVEwPOX

View: https://imgur.com/4NwK2bb

View: https://imgur.com/ahWDWw1


Do I need to find anything more specifically?

Also of note that when its at customize option from the fan control, all the numbers including the CPU are at 20 by default. So what numbers are safe to set them on?
 
4pin is pwm. Constant 12v that operates by a switch telling the fan to on/off periods. Basically making the fan into a constant state of trying to reach full speed. Better pwm fans can handle a duty cycle as low as @ 20%

3pin is analog. It operates by changing voltages to the fan. Commonly that's 5v-12v or 7v-12v. That equates to @ 40%-100% or 60%-100%

If you set an analog fan for 20%, that's @ 2.5v, which is far lower than getting the necessary voltage to turn the motor, so the fan reads 0rpm, doesn't spin.

PWM and analog don't mix well on the same controller since one needs a constant voltage and the other uses variable voltage.
 
4pin is pwm. Constant 12v that operates by a switch telling the fan to on/off periods. Basically making the fan into a constant state of trying to reach full speed. Better pwm fans can handle a duty cycle as low as @ 20%

3pin is analog. It operates by changing voltages to the fan. Commonly that's 5v-12v or 7v-12v. That equates to @ 40%-100% or 60%-100%

If you set an analog fan for 20%, that's @ 2.5v, which is far lower than getting the necessary voltage to turn the motor, so the fan reads 0rpm, doesn't spin.

PWM and analog don't mix well on the same controller since one needs a constant voltage and the other uses variable voltage.

Ok so I'm trying to look into the manual where it says the recommended values but so far it only shows this.

Fan Control Fan Speed Control Mode This feature allows the user to decide how the system controls the speeds of the onboard fans. The CPU temperature and the fan speed are correlative. When the CPU on-die temperature increases, the fan speed will also increase for effective system cooling. Select "Full Speed" to allow the onboard fans to run at full speed (of 100% Pulse Width Modulation Duty Cycle) for maximum cooling. This setting is recommended for special system configuration or debugging. Select "Stable" for the onboard fans to run at 50% of the Initial PWM Cycle in order to balance the needs between system cooling and power saving. This setting is recommended for regular systems with normal hardware configurations. Select "Quiet" to optimize for minimal fan noise and Custom to enter user-specific settings. The options are Quiet, Stable, Full Speed and Customize. When "Customize" is selected above, the settings for CPU_FAN1/ FAN2 Control, SYS FAN1/FAN2/FAN3 Control will appear and can be configured: CPU/SYS FAN# Reference Sensor This item selects which reference temperature sensor to configure. The options are CPU Temperature and PCH Temperature. The following items will be configurable: Temperature1, PWM1 ~ Temperature4, PWM4 Enter the values as needed.

I don't know much of tech but is there a specific value I should enter if I choose to customize? or is it best to use stable instead of quiet? I'm sorry because I really don't know a lot of this stuff.

I have a three pin that's connected to the motherboard directly and only two 140mm fans that are in the hub since I'm short on one fan header.
 
3pin exhaust min 65% to start, might be able to adjust that down in stages of 5% until it's obviously struggling or quits.

2x 140mm on hub, if 4wire, then set 25% minimum to start with. If 3 wire, then same as exhaust.

Just follow the connecting lead to the motherboard, its printed on the board which header, will be cpu_fan or sys_fan1 or close etc.
 
3pin exhaust min 65% to start, might be able to adjust that down in stages of 5% until it's obviously struggling or quits.

2x 140mm on hub, if 4wire, then set 25% minimum to start with. If 3 wire, then same as exhaust.

Just follow the connecting lead to the motherboard, its printed on the board which header, will be cpu_fan or sys_fan1 or close etc.

Ok so the 65% should be for both temperature and PWM1?

And likewise for 25% for the four pin fans for both temp and PWM? I can't use graph in this as I can only enter values.

System fan two is where the rear is connected and system fan 1 is where the two ml fans are connected.
 
That bios is seriously confusing things. Lol. From the way it looks for Sys_fan1, temperature 1 is the low point and temperature 2 is the high. The pwm1 and pwm2 settings should be the % setting. So according to that when the PCH (don't know why they chose that since it's the big chip with a heatsink on the upper right side) reaches 20°C the fan should be at 20% and if the temp reaches 100°C it'll be at 100%.

Temp/pwm 3 + 4 will be additional set points, so if usable you could set 1 as 20% at 20°, 2 as 50% at 30°, 3 as 60% at 40° and 4 as 100% at 100° etc. 4 setpoints representing the fan curve, as long as the values get larger in progression.

Normally motherboards will use either analog or pwm so not sure if the supermicro is pwm ONLY, meaning it'll only control 4pin fans, not 3pin on the headers. You'd need to read your manual on that.

But with a setting as low as 20 on pwm1, and your fan requiring 40 or 60 just to spin, the pwm values are what you need to adjust. The temp values only decide When the fans react to the curve. It's a physical representation of the graph.
 
Solution
That bios is seriously confusing things. Lol. From the way it looks for Sys_fan1, temperature 1 is the low point and temperature 2 is the high. The pwm1 and pwm2 settings should be the % setting. So according to that when the PCH (don't know why they chose that since it's the big chip with a heatsink on the upper right side) reaches 20°C the fan should be at 20% and if the temp reaches 100°C it'll be at 100%.

Temp/pwm 3 + 4 will be additional set points, so if usable you could set 1 as 20% at 20°, 2 as 50% at 30°, 3 as 60% at 40° and 4 as 100% at 100° etc. 4 setpoints representing the fan curve, as long as the values get larger in progression.

Normally motherboards will use either analog or pwm so not sure if the supermicro is pwm ONLY, meaning it'll only control 4pin fans, not 3pin on the headers. You'd need to read your manual on that.

But with a setting as low as 20 on pwm1, and your fan requiring 40 or 60 just to spin, the pwm values are what you need to adjust. The temp values only decide When the fans react to the curve. It's a physical representation of the graph.

Ok so to be specifically correct on this

Leave the temperature values to what they are as 20 by default. But the PWM1 value should be either 40 or 60 ? So that means all the three fans that have four pin PWM1 values have to be changed to either 40 or 60? Including even the CPU fan and the PWM2 values should be the way they are?

Is this correct?

Also, I'm looking at my manual and it doesn't mention anything about PWM other than allowing to control fan...

https://www.supermicro.com/manuals/motherboard/H270/MNL-1914.pdf
 
No. You set the temps to whatever you want the curve to be, where it starts, where it stops, depending on whether it's cpu or pch or whatever.

You set the corresponding pwm to whatever % of fan you need. If using the pwm fans, they can go down ax low as 20%, the analog fans will start at either 40% or 60% depending on the fan itself

For instance. In cpu, you could set temp for 30 and 100. You could set pwm1 for 90 and pwm2 for 100. What that means is the fan will run 90% until the cpu gets to 30°, at which point it'll slowly get faster until the fan hits 100% at cpu 100°

The 3pin fans will not spin at all until they get 5v (40% duty) or 7v (60% duty) so you'll need to start them at that voltage/% at whatever temp you decide the curve will start.
 
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No. You set the temps to whatever you want the curve to be, where it starts, where it stops, depending on whether it's cpu or pch or whatever.

You set the corresponding pwm to whatever % of fan you need. If using the pwm fans, they can go down ax low as 20%, the analog fans will start at either 40% or 60% depending on the fan itself

Ok but I just want a fixed number that pretty much says to me these settings are fine. Because I also have to mess around with the CPU fan that has both at 20 which can stress the fan for that one.

So for all my fans that have four pin pwm can you give a suggested value that is balanced including the cpu? It would help greatly because I'm unsure of what values i have to set them to
 
Nope. Because your case is not my case, your cpu is not my cpu, your coolers, fans are not my cookers, fans, the temp in your room isn't the same as mine. Your pc is yours. It's different to anyone else's. There is no set magic number that just works, other than 100. But most ppl don't like that amount of noise, so you'll need to set your fan speeds and temps according to what works for you.

If your fans are too slow, your cpu will be hot. If your temps are too high, increase the fans. If the noise is too loud, decrease the fans. You need to find your own settings that suit what you need vs what you can live with.
 
Nope. Because your case is not my case, your cpu is not my cpu, your coolers, fans are not my cookers, fans, the temp in your room isn't the same as mine. Your pc is yours. It's different to anyone else's. There is no set magic number that just works, other than 100. But most ppl don't like that amount of noise, so you'll need to set your fan speeds and temps according to what works for you.

If your fans are too slow, your cpu will be hot. If your temps are too high, increase the fans. If the noise is too loud, decrease the fans. You need to find your own settings that suit what you need vs what you can live with.

Ok I guess I'll try it out
 
So a follow up on what I have set the fans speed to

CPU fan
Temp1 at 40
PWM1 at 50
Temp2 at 80
PWM at 100

Sys fan 1
Set it as CPU temp instead of PCH temp
temp1 at 80
PWM1 at 30
temp2 at 100
PWM2 at 100

Sys fan 2
Set it as CPU temp instead of PCH temp
temp1 at 80
PWM1 at 30
temp2 at 100
PWM2 at 100

View: https://imgur.com/ZjUQhTO

View: https://imgur.com/zUVNWig

View: https://imgur.com/Po7SRFD


Are these considered safe numbers? CPU temp is at 56 degrees atleast in the bios is it also safe for the RPM fan for the CPU to be around 2000? Its a stock cooler.
 
There is no 'safe' because there is no hurt. There's nothing 'unsafe' about any fan speed, anywhere. The fan will spin upto 100%, just as it's designed to do. Doesn't matter if one fan hits 1000 rpm at 100% or another fan hits 4000 rpm at 100%. That's what they do.

Your cpu will go upto @ 100°C. It'll increase fan speeds as it gets hotter. If it gets too hot, it downclocks itself to use less power, less heat.