Question BIOS And Smart Fan Five Not Recognizing All Of My Fans

Paperdoc

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Those are 3-pin fans. Their speed can be controlled by a mobo header only if that header is configured to use the older Voltage Control Mode, rather than the new PWM Mode. Post back here the maker and exact model number of your mobo, and which mobo fan headers you have plugged those fans into. We can give you detailed instructions if you can;t figure it out yourself.
 

Paperdoc

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Thanks. Look in your mobo manual p. 27 for the configuration options available for EACH of the two SYS_FAN headers. Each of them needs to be adjusted. You have four fans, you say, and 2 of the 4 somehow change speed but not the other two. I am assuming that these four ALL are your case ventilation fans, and we are not talking about the cooling devices on your CPU chip. Is that right? THEN, since you have 4 such fans, how are they connected to two headers? Are you using simple Splitters to attach two to each of the SYS_FAN headers?

I will assume Yes for both those questions in this post. IF I am wrong, post back here the correct info for adjustment of my suggestions.

For EACH of the two SYS_FAN headers, select that header and configure as follows.
Fan Speed Control Normal
Fan Control Use Temperature Input to Motherboard,not CPU
Fan Control Mode to Voltage
Fan Stop Disabled
Temperature Warning Control 60C should be OK for the mobo, but if that generates warnings often maybe increase
Fan Fail Warning Enabled

When you have them both adjusted, use Esc to get to Main Menu, then F10 to get to Exit Menu (p. 38). Choose Save and Exit Setup to save and reboot.
 

Paperdoc

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Yes, that is a pertinent clue. If the fan hub and the fans are part of a complete system supplied that way, the Hub may or may not be designed to control fan speed. However, in that case ALL the fans connected to that hub ought to operate exactly the same way. On the other hand, if this is a third-party Fan Hub accessory, there are different things to consider. Still, all the fans on that hub should do the same thing.

So, more questions.
  1. Am I correct that these four fans all are case ventilation fans?
  2. How do you know their speeds are not being controlled? Are you relying on speeds displayed by some screen, or are you observing the fans themselves and noting differences in speeds?
  3. You say, "When I Try To Change the Fans Speed ....". How are you trying to make those changes?
  4. Is your mobo configured to manage your fan speed automatically for you, or are you setting fixed manual speeds?
 
Sep 3, 2020
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It is a third party fan hub

Yes they all are ventilation fans

if I turn them to silent mode what I'm seeing is when I look at my computer 2 running full speed and 2 running a slower speed

I'm making the changes to the fan speed through GIGABYTE's System Information Viewer because it has Smart Fan 5 Built in

also the computer is a pre built pc that has had the fans switched for new ones
 
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Paperdoc

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What you describe - 2 fans full speed, 2 fans slow on a soingle Hub - tells en that the two that run full speed all the time are 3-pin fans, but the two that can run slower are 4-pin. Check if that is right. If it is, you can NOT control the speed of a 3-pin fan that way. Tell us what maker and exact model of mobo you have so we can advise alternatives.
 

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