I'm struggling to get my head around the cooling for my current build. I understand different pressure types...

I'm struggling to get my head around the cooling for my current build. I understand different pressure types, but the issue is now PWM or non-PWM.

If I understand correctly, and pertaining to this build of mine, I've got a case that comes with three fans included but they're not PWM, they're 3 pin.

IIRC PWM is good because it's not a constant fan speed, it ramps up and down depending on required cooling. Something which is great for CPU/GPU coolers, but what about the Case itself?

I only ask because when I buy the rest of my fans, should I be getting PWM or non-PWN. If it's PWM, then I have to get another two making five, whereas if it doesn't matter I can just make do with three.

Is this something that most people overlook or do they refit all their Case fans with PWM/4 pin ones?

Bump, bls educate me.

What case do you have?

I wish to build this case and make it hover.

Phantek Enthoo Pro

>Is this something that most people overlook or do they refit all their Case fans with PWM/4 pin ones?

All my case fans are 3 pin and connected to a controller with a 3 position switch. If I wanted to use the fan headers on my motherboard, I would probably go for PWM though.

Why do you need PWM? It's not as good as software based controllers like speedfan.

>IIRC PWM is good because it's not a constant fan speed, it ramps up and down depending on required cooling

PWM is constant voltage, you get the variable speed with 3 pin fans too unless you plug them straight into your PSU and not the motherboard.

3 pins= 2 for power, 1 for sending a speed signal to your motherboard, which adjusts the voltage according to values set in the BIOS or elsewhere to get eg x fan speed at y temperature

4 pins= 2 for power, 1 for sending a speed signal, 1 for receiving a speed instruction. This means that whatever is controling the fan doesn't have to change the voltage to control the RPM because the fan is smart enough to work with instructions.

Well this is my trouble, I've got a Z170-Pro, which has good PWM support on the board (and software).

I'm just finalizing my build and realized the significance of PWM is a good question, that's actually what I'm asking.

Since all the fans that come with my case are 3 pin anyway, all I need to do is get 3 more 140mm three pin fans and that's my cooling done.

But what I was wondering is since I have motherboard support for it - and some people saying the Enthoo fan hub is shit/broken - should I be getting PWM fans? In which case I'd need to get 5 140mm four pin fans.

I suppose it would be nice to not have the fans constantly on. I don't intend to buy a fan controller, which means I won't be able to change my fan speed, right?

I think a more simpler question is, do I need PWM fans if I want fans to come on and off depending on temperature.

Is there software out there that can make non-PWM fans do this?

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This is great, so essentially there's no point in having PWM if I'm willing to do some software work instead?

Basically yes

You can control every fan through PWM (which is essentially just quickly turning on and off power - the longer it's off the slower the fan gets).
But 3 and 4 pin connectors also give a feedback signal which allows to accurately measure the rpm of the fan, which needs constant power to function correctly - so a PWM signal on the power pin will make that sensor useless.
This is why there are 4 pin fans that have an extra pin for a pwm signal which will only switch the fan on and off but not the sensor.

Well this is confusing. I'm in a similar situation to OP.

I haven't bought my components yet but I've already decided to do positive pressure cooling with five 140mm fans. Since two come stock with the case and they are three pin fans, the three I'm buying are also the same.

I'll be plugging them into the fan hub in my case and then I guess putting the fan hub SATA somewhere on the motherboard.

What I don't know is what the fans are going to do, run full blast or turn on as necessary, how does it work? Because it sounds like PWMs are the ones that do that, whereas my cheap three pin ones won't.

What do I gotta know?

Maybe you shouldn't have cheaped out, maybe you should have just bought $100 worth of case fans.

Pls no bully, what can I do in my situation anyway. Five non-PWM fans, can I just mess adjust the speed as I want from the BIOS or something? Will it let me?

It'll be fine, just buy a controller.

Did you read the thread at all?

Not him, but I think I can help.

PWM fans = Pricey, but smooth and more controllable. Recommended for OC'ing
Non-PWM fans = Annoying DC cut out and coil whine

Your case has a PWM hub on the cable side, connect all your PWM fans to that, then use the PWM hub cable to connect to your guided motherboard CPU slot (if you're lucky your cable will have a tag on it).

If you've got an Asus motherboard, use AI Suite to set up your fans.

Done.

Incorrect, the PWM hub is for three slot. Even though it's ironically named the PWM hub, any PWM fans you use with this hub won't get PWM digital control - so it's pointless. Just use three pin, non-PWM fans.

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