NZXT H440 Fan Hub Connection Advice Needed

[Vulpus Maximus]

I have just recently redone my computer using new components and everything is currently as it should be apart from one thing. I have the NZXT H440 case, which comes with a fan hub. I am using the fans that come with the case (NZXT FN V2), which are already connected to the hub. However, I do not know what to do to power it. There are two wires that are not connected. These are the molex cable, which can connect to the PSU, and the PWM cable, which can connect to the motherboard (ASUS ROG CROSSHAIR V FORMULA-Z). Should I connect both? Just the PWM? The molex?

From what I have found on the internet, connecting the molex would have the fans run at 100% at all times. This would be louder and a waste of power. Some people advise against connecting it to the motherboard because it may overload it. A motherboard's fan headers are usually 1 amp and each fan is 0.16 amps. 4*0.16=0.64 amps. This should theoretically be safe, but I am unsure and don't want to risk things.

Should I connect the PWM to the motherboard? What about the molex? Please give straight answers with reasons why.

 

[thundervore]

There were 2 versions of this case. One had a fan hub that ran all the fans 100% all the time and the other controlled them from a PWM fan header but received power from molex. Which version of the case do you have?

 

[Vulpus Maximus]

Like I said, there is a PWM cable and a molex cable, so I assume the second. The only thing I know about versions of the case is that mine is the 2015 Edition.

 

[Paperdoc]

The fan controller hub is mounted about the middle of the case. It has 4 output ports on each side, a power connection point at the bottom centre, and a connector to the mobo fan header at top left. The way it operates is that ALL fan power comes from the PSU via the power connector at the bottom, so you must connect that. (That same cable, it seems, also plugs into another small device providing power to other things like lights.) The CONTROL of all the hubs' fans REQUIRES that it gets a proper PWM signal from a mobo fan header. Your mobo's SYS_FAN headers do NOT provide this, so you need to use the Hub as its instructions say. The cable from the Hub's top left connector must go to the mobo CPU_FAN header, where it can get that signal. Then the actual CPU cooling fan MUST plug into the WHITE Port #1 of the Hub. This in the ONLY hub port that can send its fan's speed signal to the mobo header for monitoring, and it is IMPORTANT for the protection of your system that the CPU_FAN header should receive specifically the speed signal of the CPU cooling fan. All your other fans then plug into the Hub's other ports.

When things are connected this way, the temperature inside your CPU and it cooling requirements will automatically control all your fans - both the actual CPU cooler and all the case fans. They will automatically speed up or slow down, depending on how much work your system is doing and hence on the temperature inside you CPU chip.

 

[Paperdoc]

Thanks for Best Solution.

 

[thundervore]

The fan controller hub is mounted about the middle of the case. It has 4 output ports on each side, a power connection point at the bottom centre, and a connector to the mobo fan header at top left. The way it operates is that ALL fan power comes from the PSU via the power connector at the bottom, so you must connect that. (That same cable, it seems, also plugs into another small device providing power to other things like lights.) The CONTROL of all the hubs' fans REQUIRES that it gets a proper PWM signal from a mobo fan header. Your mobo's SYS_FAN headers do NOT provide this, so you need to use the Hub as its instructions say. The cable from the Hub's top left connector must go to the mobo CPU_FAN header, where it can get that signal. Then the actual CPU cooling fan MUST plug into the WHITE Port #1 of the Hub. This in the ONLY hub port that can send its fan's speed signal to the mobo header for monitoring, and it is IMPORTANT for the protection of your system that the CPU_FAN header should receive specifically the speed signal of the CPU cooling fan. All your other fans then plug into the Hub's other ports.

When things are connected this way, the temperature inside your CPU and it cooling requirements will automatically control all your fans - both the actual CPU cooler and all the case fans. They will automatically speed up or slow down, depending on how much work your system is doing and hence on the temperature inside you CPU chip.

This is not a good idea. It is only a good idea if all of your fans are the exact same model. If your CPU fan have a different speed range than the case fans it will not give correct air flow.

Looking at the motherboard you have plenty of 4 pin fan headers. I would connect the CPU cooler directly to the motherboard CPU fan header and then connect the fan hub to another 4 pin fan header. You can also bypass the fan hub completely and connect the fans directly to the many fan connections on the motherboard and control them better as Asus boards have great fan control software.

 

[Paperdoc]

thundervore has a good point. I looked up the manual for your mobo and got the info I used. But apparently I got the manual for the wrong ASUS board. Today when I hunted several times I got the right manual. Your mobo does have three CHA_FAN headers that operate in true PWM Mode, so they do provide the signal your Hub needs. It also has three OPT_FAN headers that operate similarly, but for those you must configure your own temperature curves. The CHA_FAN headers are pre-programed for your mobo, so you are best to use them and let them do their automatic fan control thing. (See later for a BIOS Setup adjustment you need to make.)

There are basically two types of fan control systems in your machine, both very similar. Each changes the speed of its fans depending on the actual temperature measured in the item to be cooled. The CPU_FAN header manipulates its fan according to a temperature sensor built into the CPU chip, so it is ideal for controlling the actual CPU cooling system. The CHA_FAN headers are based instead on a different temperature sensor built into the mobo by it maker, and so it is ideal for cooling your case.

The NZXT case manual tells you how to use its included fan Hub, and tells you to do what I advised above. That is, to connect it to the only reliable source of PWM signal, the CPU_FAN header, and then to connect all your fans to that Hub. This puts all your fans under control based on the internal CPU chip temperature. But thundervore is correct - it is better to control only the CPU cooling according to that temperature, and to control all your case ventilation fans according to the temperature of the mobo sensor. That can only be done using the Hub IF the mobo CHA_FAN header provides a PWM signal. And your mobo DOES do that, so that's the way to go.

So, first step: disconnect the lead from the Hub to your mobo CPU_FAN header. Disconnect your CPU fan from the Hub, and plug it into the CPU_FAN header. That gets the CPU cooling set up properly.

Now you have two choices. You have a Hub which can control up to eight case fans according to the output of one CHA_FAN header, and it will do that for both 3-pin and 4-pin fans. (One exception below). So you can plug the Hub's lead from the top left corner into one of your mobo's CHA_FAN headers, then plug all your case fans into the Hub's ports. In doing that, you are supposed to plug one of them into the Hub's White Port #1 that has 4 pins. I understand that that port also uses PWM Mode to control its fan, but that method can only work for a 4-pin fan. If you plug a 3-pin fan into that Port #1, it will always run full speed - this is the "exception" I mentioned. But if you have only 3-pin fans and plug them into other ports, the mobo will never get a case fan speed signal, because only Port #1 can report its speed to the mobo. If his happens to you, you may be able to go into BIOS Setup for that CHA_FAN header and tell it to ignore its fan speed so it stops sending you warning messages.

Your other option is to ignore the Hub and simply connect your case fans to mobo CHA_FAN headers. You don't tell us exactly how many case ventilation fans you have, but that might work. HOWEVER, it will not work if all your case fans are pre-installed with THREE-pin type, not 4-pin. Your mobo's CHA_FAN headers all use only the PWM Mode for control, and that cannot control the speed of 3-pin fans. So if your fans are 3-pin, go back to using the Hub, and do NOT connect one of them to the Hub's Port #1.

Finally, look at your manual on p. 3-32, the item "Chassis Fan Q-Fan Control". It indicates that the default setting is "Disabled". If that is true, you must change that to "Enabled" for the particular fan header you are using to connect the Hub, so that the mobo WILL use its automatic control feature for your case fans. After making this change, don't forget to go to the Exit menu and choose to "Save Changes and Reset".

Sorry that my earlier advice was incorrect.

 

[KnightFury]

Sorry that my earlier advice was incorrect.

Hey I just wanted to tell that you're awesome and thank you for this post