3 fans, 1 header

[Nicbloub]

Whats up everyone !
Quick question regarding fans. My case has 3 fans, but my motherboard only has 1 fan header (B450m ds3h).
What are my options here if i want to plug all 3 ? My PSU is a RM750i if that matters.

Thanks !

[Illusion of Progress]

You can adapters or probably even a full fan hub to connect them to, which would connect to your PSU.

https://www.amazon.com/CRJ-4-Pin-Sleeved-Power-Adapter/dp/B0711CR7HV

I'm not necessarily recommending that one (I presume three fans on one header is okay though), but it's an example of what you'd want.

Edit: Something like that would probably give 12V to the fans at all time, so they'd run at full speed. This may or may not be necessary and could be noisy, depending on your fans. If you want to control them, you'll need something like a hub with a switch that adjusts the fan speed/voltage.

https://www.amazon.com/Chassis-Splitter-Controller-Computer-Motherboard/dp/B08L4RD3F9

[Nicbloub]

Opprinnelig skrevet av Illusion of Progress:

You can adapters or probably even a full fan hub to connect them to, which would connect to your PSU.

https://www.amazon.com/CRJ-4-Pin-Sleeved-Power-Adapter/dp/B0711CR7HV

I'm not necessarily recommending that one (I presume three fans on one header is okay though), but it's an example of what you'd want.

Edit: Something like that would probably give 12V to the fans at all time, so they'd run at full speed. This may or may not be necessary and could be noisy, depending on your fans. If you want to control them, you'll need something like a hub with a switch that adjusts the fan speed/voltage.

https://www.amazon.com/Chassis-Splitter-Controller-Computer-Motherboard/dp/B08L4RD3F9

Where would i put the fan hub ? does it fit like a ssd ?

[PopinFRESH]

This will depend on the fans being used and the fan header on your motherboard. Many motherboards fan headers will support around 1A on a 4pin PWM fan header, however, your motherboard manual doesn't list what the maximum current is for either your CPU or SYS fan headers. As far as I can recall, I do believe Gigabyte does rate their fan headers for 1A on all of their Ryzen era motherboards.

Depending on the power draw of the fans you choose you can get a 4pin splitter cable to connect multiple fans to your fan header(s). Be sure you use the "maximum" current rating for the fan when calculating the total current draw so you account for the fan(s) running at full RPM.

If you need to figure out the current rating for a fan you can use the formula P = I * V where P is Power (Watts), I is current (AMPs), and V is voltage (Volts). The fans will typically be 12v

For example if you look at a Noctua NF-A15 PWM [noctua.at] its listed as .96W

Opprinnelig skrevet av Noctua:

Ultra-Low Power Consumption
Despite of its further improved performance, the NF-A15 PWM consumes only 0.96W of power, which amounts to a reduction of about 20% as compared to its predecessor.

So, 0.96 = I * 12
Works out to about 0.08A or around 80 milliamps.

Which, Noctua also actually provides this in their detailed NF-A15 PWM Specifications [noctua.at]

Using this fan as an example, if your fan header supports up to 1A you could put about 9 of these fans on a single header using 4pin splitters, however, I definitely wouldn't recommend doing so.

A lot of the Noctua fans also come with a 4pin Y splitter in the box, which you'll also see listed in the fan I linked above.

Opprinnelig skrevet av Noctua:

Low-Noise Adaptor (L.N.A.)
4-Pin Y-Cable
30cm Extension Cable
4 Vibration-Compensators
4 Fan Screws

If your case came with three fans you'll want to reference the manual or look up the fans to figure out what their power draw would be.

Alternatively, as Illusion of Progress noted

Opprinnelig skrevet av Illusion of Progress:

You can adapters or probably even a full fan hub to connect them to, which would connect to your PSU.

You can get a fan hub / fan controller to allow for more flexibility. A fan controller such as the Corsair Commander Pro, Thermaltake Commander FP, or EKWB Loop Connect will connect to your system via USB (usually to a USB2 motherboard header like the two on the bottom edge of your motherboard) and will have a software package that allows you to set custom fan curves based on different parameters such as CPU die temperature.

Regarding your question about where to put the fan hub / controller that all depends on your preference. Many of them will come with double sided tape to affix the hub/controller to a surface inside your case such as the back side of your motherboard tray or similar. Some cases will also come with a fan hub, or may have a version of the case which comes with a fan hub, and as such may have a mounting location for that vendors fan hub.

If you provide us with the make and model of your case someone will surely be able to help you figure out a good location to mount a fan hub/controller if you decide to go that route

[Illusion of Progress]

Opprinnelig skrevet av PopinFRESH:

Opprinnelig skrevet av Illusion of Progress:

You can adapters or probably even a full fan hub to connect them to, which would connect to your PSU.

You can get a fan hub / fan controller to allow for more flexibility. A fan controller such as the Corsair Commander Pro, Thermaltake Commander FP, or EKWB Loop Connect will connect to your system via USB (usually to a USB2 motherboard header like the two on the bottom edge of your motherboard) and will have a software package that allows you to set custom fan curves based on different parameters such as CPU die temperature.

Thanks for the additional information. I didn't know there were such things as ones that connect to USB headers. I've never had to look too much into it since my case offers connections for fans, which basically is just a fan hub, and it lets me control it with 5V, 7V, or 12V. That's what made me think of adding the edit to my prior post, since I realized a simple adapter connected to the PSU might feed them full power constantly and they may be loud depending on what fans they are (mine are, so I run them at 7V most of the time).

[PopinFRESH]

Opprinnelig skrevet av Illusion of Progress:

Opprinnelig skrevet av PopinFRESH:

You can get a fan hub / fan controller to allow for more flexibility. A fan controller such as the Corsair Commander Pro, Thermaltake Commander FP, or EKWB Loop Connect will connect to your system via USB (usually to a USB2 motherboard header like the two on the bottom edge of your motherboard) and will have a software package that allows you to set custom fan curves based on different parameters such as CPU die temperature.

Thanks for the additional information. I didn't know there were such things as ones that connect to USB headers. I've never had to look too much into it since my case offers connections for fans, which basically is just a fan hub, and it lets me control it with 5V, 7V, or 12V. That's what made me think of adding the edit to my prior post, since I realized a simple adapter connected to the PSU might feed them full power constantly and they may be loud depending on what fans they are (mine are, so I run them at 7V most of the time).

If you're adjusting the fan speed via the voltage then they are most likely DC fans, not PWM fans. The advantage of PWM fans is that they function at a consistent voltage but just "turn on and off" at different rates to adjust the RPM of the motor. Because of this they can operate at a much lower RPM without "stalling" due to insufficient power like what will happen with a DC fan.

[Nicbloub]

So ive ordered a fan hub from amazon.
In the meantime, i found a cable from my old pc.
1 side is SATA, the other side are 2 fan plug, but only 2 pins on each of them.

Can i use, temporarily, this cable to plug my 2 remaining fans without any issues ?

[Illusion of Progress]

Yes, it will work. One pin is ground and another is power. The third will be the signal for the RPM, but if it's being connected directly to the PSU, this isn't really needed. The forth pin on PWN fans is for that purpose.

Opprinnelig skrevet av PopinFRESH:

If you're adjusting the fan speed via the voltage then they are most likely DC fans, not PWM fans. The advantage of PWM fans is that they function at a consistent voltage but just "turn on and off" at different rates to adjust the RPM of the motor. Because of this they can operate at a much lower RPM without "stalling" due to insufficient power like what will happen with a DC fan.

They are.

https://www.newegg.com/phanteks-ph-f140sp-bk-case-fan/p/N82E16835709023?Item=N82E16835709023

[Viking2121]

Look at the amp rating, most fan headers can only do 1amp, if your 3 fans are rated at 0.30amps you'd be fine to run 3 fans, but much more than that I'd advise that you don't. If you burn out that header, it could take the board with it. If you pair 3 fans that can use more than 1 amp in total, the header might last for a while, but I wouldn't do it, unless the motherboard manufacture says different.

As others have said, look for a fan hub, can get alright ones for cheap these days.

[ulia]

The max current rating is probably very conservative, but it's for sure not a great idea to try your luck with it anyways. If you don't want to invest in a fan hub you could split from both the CPU_FAN and SYS_FAN1 headers, two on each which should be perfectly safe, though naturally one of the three fans will be tied to the PWM/duty cycle curves of the CPU header.

I would personally rather have fan curve control than a hardware only fan splitter, though it's a serviceable option if you don't mind the noise.

[Illusion of Progress]

I think the splitter OP is using in the meantime connects directly to the PSU as one side is SATA, so limits of power to individual motherboard headers shouldn't be a concern.

[Nicbloub]

Opprinnelig skrevet av Illusion of Progress:

I think the splitter OP is using in the meantime connects directly to the PSU as one side is SATA, so limits of power to individual motherboard headers shouldn't be a concern.

yes exactly. I plugged it into one of my sata ports from my drive cable. Seems to work fine, only its always at full speed but its ok. Itll do the job. CPU idle went from 45 to 29 degree. GPU idle went from 58 to 29 degree. Not bad.

thanks everyone, i appreciate a lot