[SOLVED] CPU Fan's ultra speed, is it because I plugged the 5 pin slots to 4 pin header?

Jan 9, 2021
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1
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Now my fan is from a Dell proprietary desktop and it has 5 pin slots and it wasnt working on the 4 pin headers, now I was going to buy a new fan until I figured out (I was trying if I can make it work somehow) that when I try to plug just the 3 pins instead of 4 pins.... I DID IT it spins, but how it spins? SOO FAST DUuDE! why tho? I know I should buy a new fan but I was just wondering why this is happening and why 5pin slots didnt work with 4 pins but works SO MUCH with 3pins?? My PSU is 600W is it because of that? Because dell prop. was 350W.

Easy explanation:
Just 4 pin slots of 5 pin slotted CPU fan -----------> 4 pinned mobo = doesn't work
Just 3 pin slots of 5 pin slotted CPU fan ------------> just 3 pins of 4 pinned mobo = does work so much and makes A LOT of noise

MOBO:
ASUS B85M-G PLUS

CPU: i7-4790

GPU: Rtx 2060

PSU: Corsair CX600M Bronze

OS: windows10 pro 64bit
 
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Solution
Look at the wiring. You may be putting the connector in the right place, but the actual wires in the connector on many Dells do Not go to the same pins.

Your motherboard cpu_fan has 4 prongs, (ground, 12v, speed, pwm). The 5pin dell is wired blank, pwm, ground, 12v, speed. So by moving the 5pin physically to line up, 12v-12v and ground-ground you are putting the motherboard speed wire where the fan pwm wire is, so the motherboard cannot change the speeds.

You will need to physically change the individual wires in the connector to match up with the correct prongs on the motherboard.

Dell does a LOT of things proprietary, they do not want you to upgrade without buying from them. So they change HOW the fan works, not WHERE it works...

Ralston18

Titan
Moderator
The problem is not because you have a 600W PSU vs 350W.

The problem is probably because you have managed to make a connection that should not be made/used.

Update your post to include full system hardware specs and OS information.

Especially the motherboard.

You need to determine the proper and applicable fan connections and connect the fan accordingly.

Otherwise there is a good chance that the 3 pin "SOO FAST" connection will not end well for your computer.
 
Jan 9, 2021
59
1
35
The problem is not because you have a 600W PSU vs 350W.

The problem is probably because you have managed to make a connection that should not be
Otherwise there is a good chance that the 3 pin "SOO FAST" connection will not end well for your computer.

You mean can it mess up the whole system?
 

Ralston18

Titan
Moderator
Yes.

PSU's provide 3 voltages: 3, 5, and 12. Polarity matters as well.

So if your pin "arrangement" is providing the wrong voltage or polarity then problems will result. Maybe not immediately.

Immediately usually involves, sparks, pops, smoke, and burning smells....

The motherboard's User Guide/Manual, the case's User Guide/Manual, and the applicable manuals for installed components show the connections that must be used.

Motherboards label each connector and each pin on that connector has a purpose and specific voltage requirements, polarity, and grounding.

Read to determine what the applicable and proper connections should be. Verify that the pinouts and connectors you are using are correct.

Sometimes adapters can be used but that, in itself, can be problematic. "Fits all" or "universal" can be a very broad interpretation....
 
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Karadjgne

Titan
Ambassador
Look at the wiring. You may be putting the connector in the right place, but the actual wires in the connector on many Dells do Not go to the same pins.

Your motherboard cpu_fan has 4 prongs, (ground, 12v, speed, pwm). The 5pin dell is wired blank, pwm, ground, 12v, speed. So by moving the 5pin physically to line up, 12v-12v and ground-ground you are putting the motherboard speed wire where the fan pwm wire is, so the motherboard cannot change the speeds.

You will need to physically change the individual wires in the connector to match up with the correct prongs on the motherboard.

Dell does a LOT of things proprietary, they do not want you to upgrade without buying from them. So they change HOW the fan works, not WHERE it works from.

And that works both ways. Adding an aftermarket fan to a Dell motherboard with a 5pin cpu_fan, you need to change the fan wires to line upto the motherboard prongs. Amazon sells adapters to do that for you. It's the only way to get Dell + Aftermarket to work as intended. ( not all Dell motherboards are like this, but there are quite a few)
 
Last edited:
Solution
Jan 9, 2021
59
1
35
You will need to physically change the individual wires in the connector to match up with the correct prongs on the motherboard.

Man you are a lifesaver! a god-sent. Watched some videos on how to remove pins from their sockets, I did changed their place accordingly by looking at the diagram you sent aand it's done. It works perfectly! Thank you very much and have a good day🌟