Question Do I need fan splitters or a fan hub?

[Leap3d]

So I am working on my first build. Everything has been ordered and a few extras ordered like more fans. Being my first build i have no clue if what I have is sufficient, overkill or just wrong. But I am worried that I may need to get either fan splitters or a fan hub. Thanks!!

Case: Fractal Design North Tempered Glass
Motherboard: ASRock X870E Nova
CPU: AMD Ryzen 9 7900X
CPU Cooler: Noctua NH-D15s Chromax.Black
4 Noctua NF-P12 redux-1700 PWM

The Case has two fans in it already giving me 6 total. From what I can tell the Board has the following for fan connectors.
- 2 x CPU Fan Connector (4-pin) (Smart Fan Speed Control)***
- 3 x Chassis Fan Connectors (4-pin) (Smart Fan Speed Control)***
- 1 x AIO Pump Fan Connector (4-pin) (Smart Fan Speed Control)***
- 1 x Water Pump Fan Connector (4-pin) (Smart Fan Speed Control)***
*** CPU_FAN1 supports the fan power up to 1A (12W).

​

 

[Lutfij]

Welcome to the forums, newcomer!

A fan hub would mean that your fans are either all managed from one header on your motherboard or you can group them into areas like intake, the CPU cooler and/or exhausts. Just an FYI, the mesh version comes with a fan hub;

North Fan Hub Missing

If you purchased the Tempered Glass version of the North case then your fan hub is not missing. It is not included in those versions of the case. The fan hubs are only included in the Mesh side panel versions of the case. As those versions of...

support.fractal-design.com

I would've had the intake set to 3x120's, the exhaust to 1x120mm and then the CPU cooler which can all be on a hub.

 

[Leap3d]

Welcome to the forums, newcomer!

A fan hub would mean that your fans are either all managed from one header on your motherboard or you can group them into areas like intake, the CPU cooler and/or exhausts. Just an FYI, the mesh version comes with a fan hub;

North Fan Hub Missing

If you purchased the Tempered Glass version of the North case then your fan hub is not missing. It is not included in those versions of the case. The fan hubs are only included in the Mesh side panel versions of the case. As those versions of...

support.fractal-design.com

I would've had the intake set to 3x120's, the exhaust to 1x120mm and then the CPU cooler which can all be on a hub.

So the case I bought is the glass version no mesh. I will edit that in the original question.
But you are saying I shouldn't need 6 fans total that 4 should be fine?

 

[Misgar]

but you are saying I shouldn't need 6 fans total that 4 should be fine?

Unless you're using an RTX 5090, 4090, 3090 or similar high power GPU, you'd probably get away with 4 fans.

If you're dissipating 450W in the GPU and 200W in the CPU (not exact figures) then you'll probably need more than 4 fans. Maybe another fan or two in the roof of the case to vent excess warm air through vents normally used by a top mounted AIO.

I've got 4 fans (2 input, 2 output) in my 7950X rig and I've not seen more than 170W in the CPU and 170W in the RTX 3060 GPU when running video renders, which push the CPU and GPU hard. Nothing seems to be overheating in the old Lian Li case which also contains 5 hard disks and 4 SSDs. No mesh panels in my case.

 

[thestryker]

With that case and using an air cooler there's no good place to put 6 fans really. Three intake and one exhaust would be the standard configuration, but you could also put one more exhaust at the top in the rear most position. It looks like the case comes with 2x 140mm fans so installing the 4 Noctua fans you got might be preferable (I'm not real familiar with the comparative performance of the two types, but generally 3x 120mm is going to move a lot more air than 2x 140mm).

 

[Leap3d]

Unless you're using an RTX 5090, 4090, 3090 or similar high power GPU, you'd probably get away with 4 fans.

If you're dissipating 450W in the GPU and 200W in the CPU (not exact figures) then you'll probably need more than 4 fans. Maybe another fan or two in the roof of the case to vent excess warm air through vents normally used by a top mounted AIO.

I've got 4 fans (2 input, 2 output) in my 7950X rig and I've not seen more than 170W in the CPU and 170W in the RTX 3060 GPU when running video renders, which push the CPU and GPU hard. Nothing seems to be overheating in the old Lian Li case which also contains 5 hard disks and 4 SSDs. No mesh panels in my case.

I am running an AMD Radeon RX 7800 XT. As of right now I have the two front fractal fans, Two Noctura on the top vent, 1 venting out the back and one pulling up from the bottom.

 

[thestryker]

I am running an AMD Radeon RX 7800 XT. As of right now I have the two front fractal fans, Two Noctura on the top vent, 1 venting out the back and one pulling up from the bottom.

Top one in the front is just causing turbulence for the CPU cooler and pulling cool air from the front intake right out the top of the case.

 

[dwd999]

I am worried that I may need to get either fan splitters or a fan hub.

*** CPU_FAN1 supports the fan power up to 1A (12W).

This is basic math, or as they used to say arithmetic. Take the total number of fans for each connector, multiply that by the max wattage of each fan (1.08 watts for each redux fan) and that's how many fans you can connect to each motherboard connector. Theoretically you could connect all of the redux fans to one connector if all of the connectors are 12 watts. And the cpu fan or even 2 cpu fans would be fine connected to the cpu1 and 2 connectors. So with a maximum of 6 case fans you would not need a hub (and since they're giving you 2 140mm fans for the front you would only have a total of 5 fans). You can use a splitter to connect the 2 front fans to one case fan connector, another splitter to connect the 2 top fans to another connector, and the rear fan on a third connector. So 2 splitters would be all that you would need and you would need to buy those separately since Noctua does not include those with Redux fans.

https://www.amazon.com/Noctua-NA-SYC1-black-NA-SYC1-chromax-Black-y-Cables/dp/B076542HBN/ref=sr_1_1?crid=143LY1BHKLAD4&dib=eyJ2IjoiMSJ9.vWoHWDPYKPqj_U_ZV9XH2-w8dN8QPOwVp693e7XRNihIurAFaENxVPgyQoPo92s7ejUQropR0gCg1oCUYGxIJzlVl9Dur508WrXrTvBhgOt__976RAUkuan4RXlRz5VVJJF0KBPMOTURW1QET2RoKYOAkyq5Og0RY5M6Dz3HRgyazSNll4eLQuAQnTYceCUl1-mfSofqaMTcr2-L8yrk_x4WTUvO8IYsEZh4vwwBnAQ.RIzKrXSPuEpvGP3YASdUG2nUdvxEapsQBNiIaodqDAw&dib_tag=se&keywords=Noctua+NA-SYC1&qid=1741145542&sprefix=noctua+na-syc1,aps,120&sr=8-1&th=1

You may also need to buy some extension cables:

https://www.amazon.com/Noctua-NA-SE...ion-Cables/dp/B07654W3F2?ref_=ast_sto_dp&th=1

 

[Paperdoc]

dwd999 has done all the math correctly. You connect your CPU cooling fans to the CPU_FAN headers so only the case vent fans are connecting to mobo CHA_FAN headers. And I agree with thestryker above: the top fan mounted very close to the front is likely to simply "steal" air brought in by the top front fan and blow it back out for no benefit. Disconnect or remove that top fan, leaving a top at the rear only.

To help with the Splitter thing, note how to tell which is which. The names sellers use often are WRONG and misguide you. A SPLITTER is a simple device with only two kinds of connections. ONE "arm" goes to a mobo CHA_FAN header to get power and control signals. Two or more "arms" with MALE (with pins) connectors are for plugging in fans. There are no other connections to be made. A HUB is a different device that can look vary similar, but it has one MORE connection "arm" that must plug into a SATA or 4-pin Molex power output connector from the PSU. This device gets all power for its fans from the PSU and uses none from the mobo host header, so it is needed when you have a LOT of fans requiring a lot of power. You do NOT need this device, OP. BOTH types of device may look like a group of cable "arms", like a small circuit board, or like a closed box with output ports in recessed holes. But the feature that distinguishes the two types is that third connection to the PSU.