• Welcome to TechPowerUp Forums, Guest! Please check out our forum guidelines for info related to our community.
  • The forums have been upgraded with support for dark mode. By default it will follow the setting on your system/browser. You may override it by scrolling to the end of the page and clicking the gears icon.

4 pin AIO MB connector for fan AND speed control?

Joined
Sep 23, 2023
Messages
765 (1.26/day)
MB I ordered has an aio connector thats 4 pin. can I connect a regular 140mm fan and are these normally configurable to run at a speed or do they just run at full speed?

I dont mind a fan runs at either 50% or full speed. better then the up and down throttling which is terribly annoying and distracting..

and how many watts/fans can you run off 1 fan connector safely?
 
Depends of the board. Usually the (AIO) pump connector is configured at full blast at stock but it's manually configurable.

And depends of the connector, check the motherboard manual to be sure. Some are spec'd for 1A/12W and others are 2A/24W or even 3A/36W.
 
MB I ordered has an aio connector thats 4 pin. can I...?
You tell us. You didn't even tell us the brand, let alone model number of the board. :(

Ruru is right. It depends on the specific board. So here's a concept that's, sadly, foreign to many - RTFM!

I frequently recommend to users of all experience levels (including myself), after selecting and ordering our parts, download the user manual and read it to become familiar with the layouts and features while we are waiting for the parts to be delivered. In many cases, it is wise to do this even BEFORE we have decided on which components we want to buy. This is nice if undecided as we may learn facts about one device that make it look more (or less) attractive than the competition - helping us to narrow down our options to the best choice for us.

So I recommend you download the user manual for this motherboard and see what the manufacturer says about that header, its capabilities and what it supports. Then do the rest of us a nice service and let us know what you have learned. That IS what forums are all about, after all, learning and sharing what we have learned.

Note a side benefit to downloading the manual now is the on-line version is frequently updated/more current than the printed one in the box. In fact, a growing trend lately is to just include a "quick start" guide in the box with instructions to visit the site and download the full user guide.
 
Note a side benefit to downloading the manual now is the on-line version is frequently updated/more current than the printed one in the box. In fact, a growing trend lately is to just include a "quick start" guide in the box with instructions to visit the site and download the full user guide.
Yeah, and that's with many other products as well. My old aircooler didn't have a paper manual at all, just had a QR core to scan with a phone and it directs to the installation manual. Worked fine but still that's too much savings of not having any kind of a paper manual.
 
4 pin is always PWM&DC and are controllable. Even 3 pin DC fan headers can be controlled as long as the option to do so exists in the bios. Doesn't matter which board it is.

I run 1.6a Delta case fans on fan headers, most are 2a and up. I've had the fans 10 years and never have broken a fan header fuse. Yes, the circuit is fused.
 
4 pin is always PWM&DC and are controllable. Even 3 pin DC fan headers can be controlled as long as the option to do so exists in the bios. Doesn't matter which board it is.

I run 1.6a Delta case fans on fan headers, most are 2a and up. I've had the fans 10 years and never have broken a fan header fuse. Yes, the circuit is fused.
Some older boards had "fake PWM" connectors, looked like PWM connectors but they weren't true PWM. Luckily I didn't stick Corsair ML fans to those since they need constant 12V input.
 
Some older boards had "fake PWM" connectors, looked like PWM connectors but they weren't true PWM. Luckily I didn't stick Corsair ML fans to those since they need constant 12V input.
Ok, but we are not generally dealing with that on common modern motherboards. Or we could talk about 2 pin fan headers as well haha.

Some fans are just junk. It's why I buy expensive Delta fans. They last year's and years and respond to any input. Have all the sound ranges you could desire from just a few decibels to over 110db!!! But moves the air to prove it.
 
Yeah, and that's with many other products as well. My old aircooler didn't have a paper manual at all, just had a QR core to scan with a phone and it directs to the installation manual. Worked fine but still that's too much savings of not having any kind of a paper manual.
I like how these companies just assume everyone has a cell phone and enjoys reading a 20 page document on it. :rolleyes:
 
MB I ordered has an aio connector thats 4 pin. can I connect a regular 140mm fan and are these normally configurable to run at a speed or do they just run at full speed?

I dont mind a fan runs at either 50% or full speed. better then the up and down throttling which is terribly annoying and distracting..

and how many watts/fans can you run off 1 fan connector safely?
My board has all fan connectors 4-pinned, PWM capable.
AIO manual said I can plug it to the CPU fan header with PWM.
So I did... and pump didnt work. Got 102C CPU temp while in BIOS... ouch!
Switched to CPU_OPT header and it worked as it should.

Every fan/pump header can support a single fan at least and can be configured from BIOS to constant speed or with a temp/% curve (PWM or voltage) target.
As for how many fans you can run form 1 header you need to dive into the board specifications for each fan header voltage/current capability as @Ruru said.
 
manual doesnt note about the AIO connector. I looked at all the pages 36. nothing there. it shows it in the diagram and notes it in the specification list. so nothing to "read in the fecking manual"

I wont mention the MB as Im embarassed as the vendor is on my never buy again list but I had no choice as I wanted to spend the least amount for my needs. i was looking for an x570 but still only having 1x16 and 1x4 when u use 2 pcie slots makes it worthless to me so no need to spend more.

its not so much an issue, even though only 3 fan headers (I is cpu). I have 7 fans and I can get a splitter (and use extension cables for neatness) that gives extra power to via a sata power cable
 
Last edited:
I wont mention the MB as Im embarassed as the vendor is on my never buy again list
Then I don't see what you are expecting from us.

Also, I don't see what difference it makes. You just told us this was on your never buy again list, then went ahead and bought anyway. The model number is just a minor detail at this point.
 
Then I don't see what you are expecting from us.

Also, I don't see what difference it makes. You just told us this was on your never buy again list, then went ahead and bought anyway. The model number is just a minor detail at this point.
so leave it. alls good. I thought some were experts here whod know.
 
It should theoretically be as usable as a regular PWM fan connector. Theoretically. See in the UEFI if it’s not locked to being only CPU_TEMP controlled for some inane reason. If it’s freely configurable you can plug whatever. Hard to say more without knowing the specific board. I am not even sure why an AIO dedicated connector is even needed - most AIOs are hooked up to CPU_FAN and CPU_OPT and work just fine.
 
It should theoretically be as usable as a regular PWM fan connector. Theoretically. See in the UEFI if it’s not locked to being only CPU_TEMP controlled for some inane reason. If it’s freely configurable you can plug whatever. Hard to say more without knowing the specific board. I am not even sure why an AIO dedicated connector is even needed - most AIOs are hooked up to CPU_FAN and CPU_OPT and work just fine.
I'm pretty sure that OP means an AIO_PUMP connector as these are pretty common these days.
 
I thought some were experts here whod know.
??? No doubt many would know, or know how to figure it out.

But without knowing the exact model number, it would be like you asking, "What tire pressure should my tires be?" without you telling us anything about your car.

My answer would the same as I did above; "You tell us!" RTFM or look inside the door frame (since most cars have a sticker there for that information).
 
??? No doubt many would know, or know how to figure it out.

But without knowing the exact model number, it would be like you asking, "What tire pressure should my tires be?" without you telling us anything about your car.

My answer would the same as I did above; "You tell us!" RTFM or look inside the door frame (since most cars have a sticker there for that information).
dude, you gave me a headache. leave it. its fine. ill figure it out.
 
LOL Fine. Good luck.
 
MB I ordered has an aio connector thats 4 pin. can I connect a regular 140mm fan and are these normally configurable to run at a speed or do they just run at full speed?

I dont mind a fan runs at either 50% or full speed. better then the up and down throttling which is terribly annoying and distracting..
Any decent modern motherboard bios will allow you to set the hysteresis for the fan ramping up or down. Just increase that above 0 and the constant up and down throttling should go away. You can also tweak the fan curve so the fans aren't constantly in a spot with a large speed delta. If you can identify at what temps this happens the most, see if the fan controls allow you to set a flat spot in that range.

and how many watts/fans can you run off 1 fan connector safely?
Assume 1A/12W unless stated otherwise by the manufacturer. Especially for el-cheapo X570 with only 3 fan headers. My X570 DARK HERO motherboard have 8 fan headers, and they are all specified at 1A/12W in the documentation. Except one water pump and one high output header which are 3A/36W. Sometimes you will also find a max total load for all headers. In the manual for my motherboard this list also show which fans are controlled how. In this case both AIO and PUMP headers are configurable in bios, but default to full speed. The rest are on auto.

This is still plenty for daisy-chaining fans (unless you use Delta fans like this nutter* earlier in the thread), for example the Noctua NF-F12 fan next to me is rated at a max load of 0.05A or 0.6W according to the label (0.03A/0.4W typical load according to their website). You can fit alot of those on a 1A header with splitters.
*) ;)

manual doesnt note about the AIO connector. I looked at all the pages 36. nothing there. it shows it in the diagram and notes it in the specification list. so nothing to "read in the fecking manual"

I wont mention the MB as Im embarassed as the vendor is on my never buy again list but I had no choice as I wanted to spend the least amount for my needs. i was looking for an x570 but still only having 1x16 and 1x4 when u use 2 pcie slots makes it worthless to me so no need to spend more.

its not so much an issue, even though only 3 fan headers (I is cpu). I have 7 fans and I can get a splitter (and use extension cables for neatness) that gives extra power to via a sata power cable
I really don't give a damn about your never buy list. I would like to help if you'd let me, but alas. GENERALLY speaking the AIO header is either 12V all the time, bound to the CPU fan header curve, or have a separate curve. Who knows which motherboard X from manufacturer Y use.

I thought some were experts here whod know.
We are experts. But we're not omniscient. Can't help without some basic details. For what it's worth I have given some general comments above

4 pin is always PWM&DC and are controllable. Even 3 pin DC fan headers can be controlled as long as the option to do so exists in the bios.
You are only partially correct. I have started running into 4-pin PWM headers that are unable to do DC control, they are constant 12V with PWM control only. If you can save 1 cent per motherboard, the bean counters will make sure it happens. 3-pin headers are either a set voltage, toggleable in bios, or dynamically controlled by bios. Without knowing the specs you can't be sure what exactly you get.
 
4 pin is always PWM&DC and are controllable. Even 3 pin DC fan headers can be controlled as long as the option to do so exists in the bios. Doesn't matter which board it is.
You are only partially correct.

Actually, both are only partially correct. It should be noted that the ATX Form Factor does not require or specify any definitive format for fan headers. The commonly found 3-pin and 4-pin connectors have become de facto standards adopted by the industries, more or less out of necessity and convenience and not through any directive. In reality, the ATX Form Factor just indicates these connectors and headers, and how they "may be" wired, are "optional".

Therefore, it really is not about the number of pins (although that certainly matters for connector compatibility) but rather the number and function of the wires. While certainly less common these days, I have seen fans with 3-pin connectors and 4-pin connectors with only 2 wires in them. Of course, in that scenario, there is no monitoring and there may, or may not be any speed (voltage) control. I have also seen 4-pin connectors with only 3 wires in them.

My point is, until the ATX Form Factor is revised again, it would be best not to assume how any particular fan works just by looking at the number of pins on its connector.
 
My board does not give any specifics (volts/amps) of the available fan headers.
Only specifies which of them are for pump(s).

7 headers
All 4-pin with both voltage/PWM control
  1. 1 x CPU fan header
  2. 1 x water cooling CPU fan header (CPU_OPT)
  3. 3 x system fan headers
  4. 2 x system fan/water cooling pump headers
I guess there is standard specs for each

1. "Simple" Fan header
2. Fan/Pump header
 
My board does not give any specifics (volts/amps) of the available fan headers.
Only specifies which of them are for pump(s).

7 headers
All 4-pin with both voltage/PWM control
  1. 1 x CPU fan header
  2. 1 x water cooling CPU fan header (CPU_OPT)
  3. 3 x system fan headers
  4. 2 x system fan/water cooling pump headers
I guess there is standard specs for each

1. "Simple" Fan header
2. Fan/Pump header
Must be a thing where some manuals just don't display actual specs.

However, Asus X570-E ROG does give the specs. And typically strix boards give the option to control PWM or DC.

Screenshot_20241229_153953_Drive.jpg
 
Back
Top