Case Fan Coversion

[skkler]

Not sure where to post this honestly. but i have a cross flow fan im wanting to put in my case. but it only has 2 wires, yes i know i could just wire it up and make it work. but i dont want it going 100% all the time. so is there a way to make it 3 or 4 pin PWM compatible? it is 12v.

[AbydosOne]

27 minutes ago, skkler said:

so is there a way to make it 3 or 4 pin PWM compatible?

There's no such thing as "3-pin PWM"; the third pin is a speed readout. Pretty much any DC fan is compatible with varying the voltage, but I'm not sure if motherboards support DC control without a tach pin (closed-loop feedback and whatnot).

 

Perhaps you could inline some Noctua low-noise adapters (or similar) and run it from the 12V from a fan header?

[skkler]

1 hour ago, AbydosOne said:

There's no such thing as "3-pin PWM"; the third pin is a speed readout. Pretty much any DC fan is compatible with varying the voltage, but I'm not sure if motherboards support DC control without a tach pin (closed-loop feedback and whatnot).

 

Perhaps you could inline some Noctua low-noise adapters (or similar) and run it from the 12V from a fan header?

i know there is no such thing, but some headers are 3 pin, some are 4 so just wanting to ensure people knew it doesnt matter if it was 3 or 4, that would want. basically want im wanting is help with a curcuit that takes the 2 wire dc from fan and turns in into a 3 or 4 wire connnect to controll the speed of the cross flow fan that way its not runnning full speed all the time

[thrasher_565]

you can 7volt,5v it, get a pot, use a resistor like AbydosOne said buy a new fan.

some mb might control it or might not thow the biso.

 

aquacomputer controller can also control it but its like $85+ so...

Edited July 11, 2024 by thrasher_565

[OhioYJ]

7 minutes ago, skkler said:

 is help with a curcuit that takes the 2 wire dc from fan and turns in into a 3 or 4 wire connnect to controller the speed of the cross flow fan

Why use the 2 wire header to begin with? Why not just use a PWM controller to start with? (Notcua for example makes a manual one you can just power from a SATA plug)

 

Also note they do make 2 to 3 pin adapters, but that still wouldn't give you speed control, other than as mentioned, you could use something like low noise adapters.

[skkler]

1 minute ago, OhioYJ said:

Why use the 2 wire header to begin with? Why not just use a PWM controller to start with? (Notcua for example makes a manual one you can just power from a SATA plug)

thats what i was trying to figure out. if i get a pwm controller i can just plug the 2 wires in it and good to go?

 

[AbydosOne]

2 minutes ago, OhioYJ said:

Why use the 2 wire header to begin with? Why not just use a PWM controller to start with? (Notcua for example makes a manual one you can just power from a SATA plug)

Because the fan in question doesn't have a PWM input?

 

Just now, skkler said:

thats what i was trying to figure out. if i get a pwm controller i can just plug the 2 wires in it and good to go?

No.

[skkler]

2 minutes ago, AbydosOne said:

Because the fan in question doesn't have a PWM input?

 

No.

okay so i would need to add something that would control the voltage for the fan then right?

[OhioYJ]

3 minutes ago, AbydosOne said:

Because the fan in question doesn't have a PWM input?

That's why I suggested a universal one. Perhaps the way I worded it that wasn't clear. The Notcua one I linked to just plugs into the PSU, then hook the fans to that, select your speed. Doesn't matter that the MB doesn't have PWM. 

 

*EDIT, oh I have it backwards, the fan is 2 wires, not the MB. 

 

Seems like a different fan would be much easier here. Fans are cheaper than any solution. 

[AbydosOne]

Just now, OhioYJ said:

That's why I suggested a universal one. Perhaps the way I worded it that wasn't clear. The Notcua one I linked to just plugs into the PSU, then hook the fans to that, select your speed. Doesn't matter that the MB doesn't have PWM. 

But that's still generating the PWM signal on pin 4 to control the fan speed... OP needs a variable DC control.

[skkler]

1 minute ago, OhioYJ said:

That's why I suggested a universal one. Perhaps the way I worded it that wasn't clear. The Notcua one I linked to just plugs into the PSU, then hook the fans to that, select your speed. Doesn't matter that the MB doesn't have PWM. 

the mother board does have PWM, the fan i want to use doesnt. im wanting to find a way to give the fan PWM control to plug it into the motherboard

[thrasher_565]

something like this would work but i mean you can buy a new fan cheaper...

this

fans

1fan

Edited July 11, 2024 by thrasher_565

[skkler]

find me a cross flow fan with pwm control and i buy it  

[thrasher_565]

2 minutes ago, skkler said:

find me a cross flow fan with pwm control and i buy it  

what you mean crossflow? like an axle fan?

 

[skkler]

9 minutes ago, thrasher_565 said:

what you mean crossflow? like an axle fan?

 

 

like this

 

[thrasher_565]

1 minute ago, skkler said:

 

like this

 

oh...ok so why do you want to use this in the pc? and how many amps is it?

 

[skkler]

Just now, thrasher_565 said:

oh...ok so why do you want to use this in the pc? and how many amps is it?

 

working on designing a case and want to use the fan since it has a high CFM at relatively low noise. and its 1 amp

 

[thrasher_565]

8 minutes ago, skkler said:

working on designing a case and want to use the fan since it has a high CFM at relatively low noise. and its 1 amp

 

well 1amp might work i would use a molex controller then as molex can do a bit more power. something like this maybe

this

 

the thing about pots is i herard they kill them selfs over time atlest the cheap ones do.

 

Edited July 11, 2024 by thrasher_565

[skkler]

54 minutes ago, thrasher_565 said:

well 1amp might work i would use a molex controller then as molex can do a bit more power. something like this maybe

this

 

the thing about pots is i herard they kill them selfs over time atlest the cheap ones do.

 

i seen them, the issue with them,. is they dont have any circuitry on them to be able to controller the fan,

[TPCEA]

9 hours ago, skkler said:

i seen them, the issue with them,. is they dont have any circuitry on them to be able to controller the fan,

Thrasher is right.  You are going to have to buy something expensive, design a controller that works with PWM and let's you program the relevant fan specs, or just run it off the PSU. Linus reviewed one of those fans not too long ago. 

[thrasher_565]

11 hours ago, skkler said:

i seen them, the issue with them,. is they dont have any circuitry on them to be able to controller the fan,

one has a pot witch is a variable resistor the other has a switch for low mid and hi

the switch switches between resistors. or you can simply 7volt it 5volt it 12volt it and off with a toggle switch. could add some resistors too.

 

if you want software controller then an aquacomputer controller can do that just cost like $85+ thow i dont no about the 1amp...

 

this stuff is basic electronics and if you dont under stand it then maybe this project is not for you... or use a different fan.

 

Edited July 11, 2024 by thrasher_565

[skkler]

On 7/11/2024 at 9:52 AM, thrasher_565 said:

one has a pot witch is a variable resistor the other has a switch for low mid and hi

the switch switches between resistors. or you can simply 7volt it 5volt it 12volt it and off with a toggle switch. could add some resistors too.

 

if you want software controller then an aquacomputer controller can do that just cost like $85+ thow i dont no about the 1amp...

 

this stuff is basic electronics and if you dont under stand it then maybe this project is not for you... or use a different fan.

 

funny you say that lol, i dont know basic electronics that well. thats why im doing this. to challenge my self and learn while getting something i can use out of it