Fractal R6 case fan hub experiences/thoughts

[rocks911]

I am connecting the fans in my build and I have at least one question and probably more. I have installed an ASUS Z370 _ E mobo in a Fractal R6 case. I also installed a Noctua NH-D15s CPU cooler with one fan. The R6 case has 3 case fans. The Noctua fan is a 4 pin and the 3 case fans are 3 pin.

The fan hub on the case is supposed to be plugged into the CPU_FAN header on the mobo and then all fans are supposed to be plugged into the fan hub. If I understand this correctly then all fans will respond to an increase in CPU temp. by spinning up. The 3 case fans will be a slave to the CPU_FAN essentially.

I dont know that I want my fans set up this way. I might be better off just connecting the fans to the mobo and just disregard the fan hub.

Any thoughts would be appreciated.

 

[anotherdrew]

Fractal makes cool cases, but not everything they do always makes sense.

I looked over the manual and it is not clear exactly how the fan hub works. If the case fans really do alternate speed with the CPU, that could become annoying. I would try it and see (I'm a curious person), but you might be better plugging the CPU fan directly into the motherboard and plugging the fan hub into CHA_FAN1 (near the memory). That way you do get some increase in speed as temps go up, but not as drastic as CPU temperature fluctuations.

 

[Paperdoc]

I agree with you, OP. The case ventilation fans really should be governed by the temperature sensor on the mobo, not the one inside the CPU chip, so they should be connected to the CHA_FAN headers. You don't need the Fractal Design Hub for this, so ignoring it is a good idea. Since they are 3-pin fans, your simplest alternative is a SPLITTER. A Splitter has only two types of arms. One ends in a female fan connector that plugs into the mobo CHA_FAN header. The other two (or three) are output arms ending in male (with pins) connectors to plug your fans into. Do NOT get a Hub - those items are different and have a third arm type that must connect to a power output from the PSU. They generally cannot be used with 3-pin fan systems.

You may find it hard to find a 3-pin fan Splitter, but a 4-pin Splitter will do just fine - your fans simply won't use Pin #4. You will see that most Splitters have all their pins on only ONE of the output arms, and the other outputs omit Pin #3. This is the correct way, and does not affect fan control at all.

The fans with your case pull 0.2 A max, so three of them using a Splitter on one CHA_FAN header is quite acceptable. For that you could get something like this

https://www.newegg.com/Product/Product.aspx?Item=N82E16812423163&cm_re=coboc_fan_splitter-_-12-423-163-_-Product

or this

https://www.newegg.com/Product/Product.aspx?Item=N82E16882422016&cm_re=coboc_fan_splitter-_-82-422-016-_-Product

Alternatively you could use a two-output Splitter like this

https://www.newegg.com/Product/Product.aspx?Item=N82E16812423160&cm_re=coboc_fan_splitter-_-12-423-160-_-Product

for two of your fans on one header, and connect the third fan to the other CHA_FAN header.

Whichever way you do it, see your mobo manual p. 3-7. For EACH of the CHA_FAN headers you use, set it to use DC Mode for 3-pin fans, and choose a temperature sensor. I suggest the general motherboard sensor, although there are a couple others available for specific mobo components. Remember to SAVE and EXIT.

 

[anotherdrew]

I agree with Paperdoc, except that I would skip getting the splitter ... the fan hub has a 1 to 3 spiltter built in (with 3 pin outputs). Why spend money on something you already have. Feed CHA_FAN1 to the hub along with some extra power and use the 3 3pin connectors for your 3 case fans. Done.

 

[Karadjgne]

The fan hub has no difinitive use. You can use it from the cpu_fan header which when combined with the 2 stock fans, will spin all the fans according to the hub setting. Not everyone uses a pwm powered cpu fan. The older NH-D14 used analog 3 pin fans, so had issues with newer design boards where the cpu_fan header was dedicated pwm. The case fan hub gets around that restriction by allowing user settings, low/mid/high (7v/9v/12v) settings. So for a basic, stock type build, using the stock or analog cpu cooler, it works.

Doesn't mean you need it for a more thought out build. I have the same hub in my Define R5, don't use it, don't need it. But it's there if I did have a use for it. As is, I use asus fanXpert and SpeedFan, which are preset with my curves to automatically raise/lower fan rpm according to case temps, not cpu temps.

Honestly, you shouldn't use cpu_fan header for anything other than it's intended purpose, or your case fans will be constantly ramping up, even at idle, as windows will bounce 20°C+ easily, just sitting at idle.

 

[Paperdoc]

There's a reason I agreed with OP about forgetting the included Hub. If has an interesting design. It has three 4-pin fan outputs for use with 4-pin PWM-controlled fans, of which one returns its fan's speed to the host mobo header. The instructions say that header should be the CPU_FAN header, and hence the fan plugged into Hub Port #1 should be the actual CPU cooler. The Hub also has three 3-pin fan ports that use Voltage Control Mode, based on the PWM signal it gets from the CPU_FAN header. However, as OP correctly understands, that puts ALL of its fans, including all case ventilation fans, under guidance by the temperature sensor inside the CPU chip.

Now, the simple alternative appears to be to connect the actual CPU cooler directly to the CPU_FAN header, and them connect the Hub to a mobo CHA_FAN header that is configured to use PWM Mode so it can deliver the PWM signal the Hub requires. This puts those fans under guidance by a temperature sensor on the mobo. The potential problem I see here is that several users on this site have reported that the Hub apparently fails to work if there is no actual PWM 4-pin fan plugged into its Port #1. And OP has only three 3-pin case ventilation fans to plug in. So, to make it work, OP would have to buy an additional 4-pin fan and mount it somewhere. I consider it simpler and cheaper to ignore the Hub and buy one or two Splitters to connect those 3-pin fans to CHA_FAN headers, configuring them to use DC Mode for control.

Hey, OP, thanks for Best Solution.

 

[Karadjgne]

Exactly. For the most part it's just another gimmick. Handy if you have a use for it, but otherwise it's generally skipped in favor of separate controls for cpu and case fans.

What I meant was that you can also use it via cha_fan header, and still use a pwm fan in Port #1, but would then be regulated by that particular headers sensor, not the cpu's. Thereby having control over just the case fans, allowing for use of AIO's which also need the cpu_fan header, and/or a pwm aircooler separate from case fan temps.

 

[Paperdoc]

^ You are right. If you are going to use at least one PWM type fan among a group for case ventilation, this Hub has some very handy features to use. I just happened in this particular case that OP didn't plan to get a 4-pin case fan.

 

[Karadjgne]

I personally like the fact that fractal took the time and effort to include the hub, even if I don't use it. I've seen far too many micro-B boards with just a cpu and 1 cha_fan header. The case included hub alleviates a whole bundle of issues there. It's a nice touch in my book.

 

[Paperdoc]

It also provides some solution for a common dilemma. MANY cases include ventilation fans, but they are 3-pin (VERY slightly cheaper), which means they are NOT suitable for use with nearly all Hubs. This Hub can deal with both fan designs.

 

[Karadjgne]

Yep. One of those little things overlooked on many cases. Kinda like when some designs used stock fans with molex plugs, rendering many ppl to scrap them in favor of motherboard controllable fans. Just an extra expense. This hub offers options.