[SOLVED] Built in Molex case fans

Aug 11, 2019
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So I am trying to build a computer for my wife and the case she likes, that I am considering buying has 4 built in molex fans. The problem with that is people say these run full blast all the time. I read it may be possible to use an adapter to plug them into my motherboard, or even get a controller for them. What would you guys suggest. This is the build I have so far: https://pcpartpicker.com/user/Arvais211/saved/#view=2nF3t6
 
Solution
From pictures of the case, it looks like the 200mm fan can be removed and replaced with two smaller fans, or just completely removed. If you want to keep the LED on the fan, you can get some corsair RGB fans or something.

Some cases have fan mounts which support different fan sizes.
Noctua makes some great fans, and the NF-P12 is what I would recommend if you want a noctua fan.
bequiet makes quiet fans, and the Silent Wings 3 120mm fan is what I would recommend from them.
If you want LEDs, Corsair LL120's are great 120mm RGB LED fans.
For pure budget, I would get some NF-P12's. They don't look beautiful, but they aren't as bad as Noctua's old brown fans.
Also you probably don't even need 4 120mm fans. Again, from pictures of the...
It is true that if you plug the molex connectors into the PSU, it will always run at full blast.
As far as I know, you cannot control a molex fan with a pwm header (on the motherboard), because the only pins molex and pwm have in common are 12v power and ground, which doesn't allow control.
I don't know of any fan controllers which use molex.
Check whether the fans are pwm with a pwm to molex adapter on them.
If they are, remove the adapter and plug the headers into the motherboard and it should work fine.
 
Case manual is here.

It appears that the fans are standard 12V fans, and are intended to be directly connected to the PSU. As such, they will run at full speed. It may be possible to run the fans from a variable voltage controller, but there's the matter of adapting the fans to the controller pinouts, which may be more hassle, and cause more of a rat's nest of wiring inside the case than you want to deal with.

For the 120mm fans, you may actually be better-off just replacing the fans with PWM fans, and connecting them to the motherboard fan headers, and trimming the fan curves to your wife's preferences.

I know that, if I handed my wife a computer with 4 - 12V fans, running at full speed, she would be handing my head back to me in a plastic shopping bag. Then again, your wife may be less sensitive to fan whine.
 
Aug 11, 2019
10
1
15
Case manual is here.

It appears that the fans are standard 12V fans, and are intended to be directly connected to the PSU. As such, they will run at full speed. It may be possible to run the fans from a variable voltage controller, but there's the matter of adapting the fans to the controller pinouts, which may be more hassle, and cause more of a rat's nest of wiring inside the case than you want to deal with.

For the 120mm fans, you may actually be better-off just replacing the fans with PWM fans, and connecting them to the motherboard fan headers, and trimming the fan curves to your wife's preferences.

I know that, if I handed my wife a computer with 4 - 12V fans, running at full speed, she would be handing my head back to me in a plastic shopping bag. Then again, your wife may be less sensitive to fan whine.
After looking at it again it actually has 1 x 200mm fan and 4 x 120 fans. I may take that suggestion on replacing the 4 x 120mm fans with PWM fans. I am assuming that the 200mm, which I probably wouldn't want to replace since it is the LED fan, would still be attached to the PSU and run all the time? Still be 4/5 quieter, lol. Thanks guys for the replys. Any good, budget friendly fan brands you guys recommend? Also, I was going fairly cheap on the cpu fan cooler, is that something that ok, or is it really better to get a little better cooler? Again, I'm trying to penny pinch in some areas since this rig is already over $1000 mark.
 
From pictures of the case, it looks like the 200mm fan can be removed and replaced with two smaller fans, or just completely removed. If you want to keep the LED on the fan, you can get some corsair RGB fans or something.

Some cases have fan mounts which support different fan sizes.
Noctua makes some great fans, and the NF-P12 is what I would recommend if you want a noctua fan.
bequiet makes quiet fans, and the Silent Wings 3 120mm fan is what I would recommend from them.
If you want LEDs, Corsair LL120's are great 120mm RGB LED fans.
For pure budget, I would get some NF-P12's. They don't look beautiful, but they aren't as bad as Noctua's old brown fans.
Also you probably don't even need 4 120mm fans. Again, from pictures of the case, I see two top exhaust fans and one back exhaust fan. I believe there is one intake fan in the front or bottom, but I'm not too sure on that.
What I would do is remove one of the top exhaust fans, as two top exhaust fans is pretty overkill.
If there is no intake fan already, I'd suggest adding one if there is a mount.
 
Solution
Aug 11, 2019
10
1
15
From pictures of the case, it looks like the 200mm fan can be removed and replaced with two smaller fans, or just completely removed. If you want to keep the LED on the fan, you can get some corsair RGB fans or something.

Some cases have fan mounts which support different fan sizes.
Noctua makes some great fans, and the NF-P12 is what I would recommend if you want a noctua fan.
bequiet makes quiet fans, and the Silent Wings 3 120mm fan is what I would recommend from them.
If you want LEDs, Corsair LL120's are great 120mm RGB LED fans.
For pure budget, I would get some NF-P12's. They don't look beautiful, but they aren't as bad as Noctua's old brown fans.
Also you probably don't even need 4 120mm fans. Again, from pictures of the case, I see two top exhaust fans and one back exhaust fan. I believe there is one intake fan in the front or bottom, but I'm not too sure on that.
What I would do is remove one of the top exhaust fans, as two top exhaust fans is pretty overkill.
If there is no intake fan already, I'd suggest adding one if there is a mount.
Thanks for the reply and the great suggestions. I also decided the mobo I had needed a slight upgrade as it didn't support rgb and was very limiting on pwm fan headers. Found a gigabite Z390 UD that is $10 more and seems more accommodating. May not even need a split header if I go with the 140mm fan attached to the psu by molex and the other three fans (I agree 4 is probably overkill) look like there are enough headers.
 
As to fan brands, I do happen to have a case full of the Be-Quiet! Silent Wings fans (6 of the 140mm jobbies) and I can attest to their silent nature; however, if you go with Noctuas, I'd imagine that you would be in good stead as well.

I used to have a case full of full speed fans, and I didn't mind it because I wear headphones for my computer audio. My wife, on the other hand hates headphones, and hated my old build with a purple passion.

She's a LOT happier lately.....not sure why.
 
Yes, a 4 pin molex connected fan will run at full speed.

I might suggest for your build that you try using only the 200mm fan as intake, and remove all of the others.
A 200mm fan moves a lot of air and is relatively quiet.

In the event that you wish to trade off airflow for quiet, you can buy a rheostat type controller that can dial in whatever speed you want.
You can also buy low speed adapters that reduce the voltage to 7 or even 5w.
If your fans have a yellow speed sensing wire, you can buy an adapter like this:
https://www.newegg.com/p/N82E168122...x_to_3_pin_fan_adapter-_-12-201-036-_-Product

And FWIW, the cooler you listed is totally inappropriate for a 9600K.
I might suggest a cryorig H7 or other tower type cooler with a maximum height of 155mm that your case allows.
 
I have two noctua NF-P14S's (the 140mm version of the NF-P12) as intake fans on my pc (pictured in my profile picture), and they they are quiet, but not silent at idle, and can get moderately noisy at full load (apparently it tops out at 25.8 db), but so far they have never actually hit full load, no matter how much long term load I put on the system, because the temps never get high enough, due to how much air my fans move in the first place.
Unless your wife is really picky about noise, you can stick with noctua fans.