Build Advice a mistake for AIO water cooling

[Mkazem]

I strongly advise you to read manuals of your AIO water cooler before doing this (I used Corsair H100i V2). this is the mistake that i made as a newbie and now found my stupid mistakes.

If the manual says to plug pump cable into CPU_FAN header you should just do that. ignore PUMP header provided by your fancy motherboard.

if you plugged the pump into PUMP header and plugged fans to CPU_FAN header that's just wrong. because fans mounted on radiator don't directly interact with CPU, all they have to do is to move fresh air into radiator fins so that fins remain cool. fins take heat from coolant and coolant takes the heat from CPU.

So it doesn't matter if your CPU temp is 25C or 80C, putting fans at full speed wont do anything other than making a lot of noise (and wasting energy). you would be fine with fans running at 30% and CPU temp at 70C.

Pump is doing the main job and radiator provides great cross section for releasing the heat. so your fans won't need to run aggressively.

with the wrong setup like above you miss the very benefit of water cooling, that is MUCH less noise regardless of CPU temp.

Important Notice! make sure that your pump is running at full speed by disabling Q-fan control of your CPU_FAN header. usually pumps are designed to run at constant speed and it will probably damage your cooler if you don't do this. (refer to your AIO cooler manual to make sure)

 

[idnom]

I have a sealed H100i pro rgb, if I use this and not planning to use the stock fans should I connect the 3 pins fan connector to CPU_FAN? or do I just need to connect the SATA Power connector? does the 3 pins control the pump and not the fans included?

 

[rubix_1011]

Some of this is true, but I want to clarify a few things.

How your fan headers react on your motherboard are usually defined either by the CPU core temperature, or by any number other thermal sensors on the board. Most newer motherboards can allow you to determine what sensor each header reads and allow the fan curve to be set either automatically or manually. This can be different across motherboard manufacturers and models.

Pump speed for an AIO likely can run at 100%, although many of them are PWM capable - just understand that pump speed does not need to ramp up and down quickly - set your fan curves for a flatter response if using PWM. Otherwise, PWM pumps are intended to be run according to reported temps...it isn't what I would do, but many people do.

A pump alone isn't going to be the lone solution for removing heat from a CPU - you still need airflow over the radiator to do the actual heat exchange...the flow rate is just going to move more coolant to exchange out more quickly. I say 'quickly' but most AIO coolers have very, very poor flow rates, so it is really a difference of 'low' and 'not all the way stopped'.

 

[Mkazem]

I have a sealed H100i pro rgb, if I use this and not planning to use the stock fans should I connect the 3 pins fan connector to CPU_FAN? or do I just need to connect the SATA Power connector? does the 3 pins control the pump and not the fans included?

I took a quick look on manual. It says

• Connect pump power cable to an available SATA power plug
• Connect pump tach cable to the CPU_FAN header on your motherboard
• Connect each fan to the shrouded 4 pin connectors on the pump

So you have probably three wires coming of the pump, one is SATA cable that should be connected to an available SATA power plug (not sure what is that because H100i v2 didn't have that)

another cable is 3 pin connector that should be connected to CPU_FAN header. even if your motherboard has dedicated PUMP header don't use that. those are for custom liquid cooling not AIO coolers. remember to disable Q-fan control for CPU_FAN in bios as well.

last cable splits to two 4 pin male connectors, your two fans mounted on the radiator should be connected to these 4 pin male connectors. speed of the fans is then controlled by the pump and the software "iCUE" depending on coolant temperature.

 

[Gmoney06ss]

I never had a single issue running my h100i v2 with the pump hooked up to the pump header on the mobo and fans hooked up to cpu_fan header. Ran this way for over 2 years before taking the jump into custom loop cooling.

The more air you fans move over the radiator the more efficient it cools. My pump was set with corsair link until icue was released. The pump would run at a fixed rpm based on mode, wether it was quiet,performance or extreme. It ran 1350 in quiet/balanced and at 1950 in performance mode. Fan speed was based on temp, with a gradual increase of fan speed until a certain temp and then capped at about 80%.

I've only dealt with a couple pumps for water cooling, but none have had a 4 pin connector, all were sata or Molex. So I believe that those pump header are for aio cooler pumps.

So while the pump may be doing the main cooling(it's not) the fans still play an integral part of the cooling process along with the rad itself. Take the fans away and see what happens to the temps after it reaches capacity.

Unless specifically instructed by the maker of the aio kit to not use the pump header for the pump, there is no harm in doing so.

 

[idnom]

I took a quick look on manual. It says

• Connect pump power cable to an available SATA power plug
• Connect pump tach cable to the CPU_FAN header on your motherboard
• Connect each fan to the shrouded 4 pin connectors on the pump

So you have probably three wires coming of the pump, one is SATA cable that should be connected to an available SATA power plug (not sure what is that because H100i v2 didn't have that)

another cable is 3 pin connector that should be connected to CPU_FAN header. even if your motherboard has dedicated PUMP header don't use that. those are for custom liquid cooling not AIO coolers. remember to disable Q-fan control for CPU_FAN in bios as well.

last cable splits to two 4 pin male connectors, your two fans mounted on the radiator should be connected to these 4 pin male connectors. speed of the fans is then controlled by the pump and the software "iCUE" depending on coolant temperature.

Thank you for the inputs, sorry I'm still new with this.

1. the SATA cable is for pump power?
2. and connector for CPU_FAN is for controlling the pump? or fans only? or both?

I'll be using different type of fans for this with different fan controller..how do I control the pump?

 

[Mkazem]

Thank you for the inputs, sorry I'm still new with this.

1. the SATA cable is for pump power?
2. and connector for CPU_FAN is for controlling the pump? or fans only? or both?

I'll be using different type of fans for this with different fan controller..how do I control the pump?

1. the manual says its the pump power cable, probably they did that because of mistakes like this, the Q-fan control could cause less power to be fed to the pump which is not good. so I think they separated the power source to solve this problem.

i said "probably" because that's just a guess

2. It's probably just for letting your computer to boot up. or maybe some RPM readings are involved. note that RPM reading of pump by motherboard may not be correct.

for me the motherboard shows 900rpm for the pump while Corsair Link/iCue shows 1800rpm for pump.

I'll be using different type of fans for this with different fan controller..how do I control the pump?

there are two connectors coming off the pump for controlling two fans mounted on the radiator. fans should be controlled based on the liquid temperature and not the CPU temps.

for controlling the pump and fans you should install iCUE. the default mode is Quiet i think, I haven't seen noticeable temp differences between Quiet and Extreme mode.

I never had a single issue running my h100i v2 with the pump hooked up to the pump header on the mobo and fans hooked up to cpu_fan header. Ran this way for over 2 years before taking the jump into custom loop cooling.

The more air you fans move over the radiator the more efficient it cools. My pump was set with corsair link until icue was released. The pump would run at a fixed rpm based on mode, wether it was quiet,performance or extreme. It ran 1350 in quiet/balanced and at 1950 in performance mode. Fan speed was based on temp, with a gradual increase of fan speed until a certain temp and then capped at about 80%.

I've only dealt with a couple pumps for water cooling, but none have had a 4 pin connector, all were sata or Molex. So I believe that those pump header are for aio cooler pumps.

So while the pump may be doing the main cooling(it's not) the fans still play an integral part of the cooling process along with the rad itself. Take the fans away and see what happens to the temps after it reaches capacity.

Unless specifically instructed by the maker of the aio kit to not use the pump header for the pump, there is no harm in doing so.

I don't have experience with any liquid cooler other than what i currently have for 2 years. I had the wrong setup until recently.

I've only dealt with a couple pumps for water cooling, but none have had a 4 pin connector, all were sata or Molex. So I believe that those pump header are for aio cooler pumps.

Yes, the pump power cable is 3 pin but there are two 4 pin connectors coming off the pump as well. its for controlling fans on the radiator.

So while the pump may be doing the main cooling(it's not) the fans still play an integral part of the cooling process along with the rad itself. Take the fans away and see what happens to the temps after it reaches capacity.

if the pump fails your CPU would reach 100C in very short time. and believe me I had that experience, but some how I could revive my cooler. I made a question about that here as well

two fans were running 100%, the CPU was at 100C because there was no flow, and that rendered the radiator and fans completely useless. I agree that radiator and fans also play significant rule, all of them are important but pump is the heart

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You may get 1~2C lower temps but that doesn't worth the loud noise. With the new setup i wont notice my CPU reached 70C, nice and quiet.

I think it's better for fans to run depending on liquid temperature, they are not designed to cool down the CPU directly. fans can't help when the CPU reaches 100C, all they can do is to cool down the radiator.

I'm looking for a way to get a warning about high CPU temps though. Corsair Link had that feature but iCue doesn't seem to have that yet. ( stick to iCue because that's newer )

---

Your pump speed for H100i v2 seems lower than mine by the way. is that what Corsair Link/iCue showed? for me it floats around 1800 Quiet and ~2800 in performance mode.

 

[idnom]

@Mkazem Thanks bro.

 

[Paperdoc]

First, let me echo OP's major point. READ and the manual for your system and DO what it says. Beyond that, I see some misunderstandings in this thread, so let me fill in details to help.

Many AIO liquid cooling systems are designed so the the PUMP unit always runs at full speed, and all control of CPU cooling is done by manipulating the speed of the FANS mounted on the radiator. (There are some systems that also manipulate the pump speed, but those are less common, and that is done usually by the custom software utility supplied with the system.) There are some systems that use the mobo CPU_FAN header to control the radiator fans, and use a different header to power the pump. The Corsair H100i V2 system does NOT do it that way. The pump unit actually has FOUR connections to it for the several functions. It has one cable that plugs into a SATA power output from the PSU to provide power to the system. It has a two-output cable into which the radiator fans are connected to provide power AND speed control for them. It has one cable ending in a THREE-pin fan connector that goes to the mobo CPU_FAN header and its main function is to send the PUMP's speed to that header. NOTE that this is important for FAILURE DETECTION. The CPU_FAN header normally monitors very carefully the speed signal from its "fan" (or pump in this case). If it gets no speed (or sometimes, a speed lower than some trigger limit), it sends out a prominent warning and, in some designs, may take drastic action to shut down the entire system without even waiting for the CPU's internal sensor to indicate high temperature. This is to protect the expensive CPU from damage by overheating if cooling fails. So it is important to give that header a meaningful signal indicating cooling system functions, and the PUMP speed is suitable for this system.

This paragraph does NOT apply to the Corsair H100i V2 system, I believe, but it does to some other designs. Some use an interesting feature of how fan systems work. The older 3-pin fan design varies the voltage supplied by Pin #2 of the header to change fan speed. The newer PWM system for 4-pin fans supplies a constant +12 VDC on that Pin #2, and then the new PWM signal on Pin #4. A 4-pin fan plugged in that way has a special chip that will use the PWM signal internally to modify power from from the +12 VDC supply and change its own speed. A 3-pin fan, however, has no such internal chip and no connection to Pin #4, so it does NOT modify the power and always runs at full speed because that's the voltage it always receives from Pin #2. In some maker's designs the cable to the CPU_FAN or to the PUMP header has ONLY three pins, and thus its PUMP acts like an older-type 3-pin fan and runs full speed. HOWEVER, many such headers CAN be configured to use either older DC Mode, newer PWM Mode, or to adjust itself automatically to whatever type of fan is connected. The instructions with those systems MAY tell you how to adjust these settings, and you must do that to ensure the header uses the proper Mode so that the pump power supply from Pin #2 is correct. The Corsair H100i system, I suspect, does NOT do it this way. It has a direct connection to a good constant +12 VDC supply through its SATA source from the CPU and uses that for pump power, as well as for radiator fan power.

The Corsair H100i V2 system also has a FOURTH connection that OP has not mentioned. There is a cable to connect from a socket on the pump to a mobo USB2 port. In addition, you are instructed to download the free Corsair Link software utility and install it. THIS utility takes over all control of the H100i V2 cooling system - the system does NOT rely on the mobo controls for this. The Link utility communicates with the pump unit using that USB cable, and uses information from the mobo (especially the CPU chip's internal temperature) for its own methods of controlling the FANS on the radiator and monitoring for failures.

So, there are several ways that AIO cooling systems may be designed and controlled. Corsair uses one system in the H100i V2 product, and actually has used other systems in some of its other products. No matter whose system you buy, as OP says, it is IMPORTANT to read the instructions and follow them so that your system can do its job as designed.

 

[idnom]

First, let me echo OP's major point. READ and the manual for your system and DO what it says. Beyond that, I see some misunderstandings in this thread, so let me fill in details to help.

Many AIO liquid cooling systems are designed so the the PUMP unit always runs at full speed, and all control of CPU cooling is done by manipulating the speed of the FANS mounted on the radiator. (There are some systems that also manipulate the pump speed, but those are less common, and that is done usually by the custom software utility supplied with the system.) There are some systems that use the mobo CPU_FAN header to control the radiator fans, and use a different header to power the pump. The Corsair H100i V2 system does NOT do it that way. The pump unit actually has FOUR connections to it for the several functions. It has one cable that plugs into a SATA power output from the PSU to provide power to the system. It has a two-output cable into which the radiator fans are connected to provide power AND speed control for them. It has one cable ending in a THREE-pin fan connector that goes to the mobo CPU_FAN header and its main function is to send the PUMP's speed to that header. NOTE that this is important for FAILURE DETECTION. The CPU_FAN header normally monitors very carefully the speed signal from its "fan" (or pump in this case). If it gets no speed (or sometimes, a speed lower than some trigger limit), it sends out a prominent warning and, in some designs, may take drastic action to shut down the entire system without even waiting for the CPU's internal sensor to indicate high temperature. This is to protect the expensive CPU from damage by overheating if cooling fails. So it is important to give that header a meaningful signal indicating cooling system functions, and the PUMP speed is suitable for this system.

This paragraph does NOT apply to the Corsair H100i V2 system, I believe, but it does to some other designs. Some use an interesting feature of how fan systems work. The older 3-pin fan design varies the voltage supplied by Pin #2 of the header to change fan speed. The newer PWM system for 4-pin fans supplies a constant +12 VDC on that Pin #2, and then the new PWM signal on Pin #4. A 4-pin fan plugged in that way has a special chip that will use the PWM signal internally to modify power from from the +12 VDC supply and change its own speed. A 3-pin fan, however, has no such internal chip and no connection to Pin #4, so it does NOT modify the power and always runs at full speed because that's the voltage it always receives from Pin #2. In some maker's designs the cable to the CPU_FAN or to the PUMP header has ONLY three pins, and thus its PUMP acts like an older-type 3-pin fan and runs full speed. HOWEVER, many such headers CAN be configured to use either older DC Mode, newer PWM Mode, or to adjust itself automatically to whatever type of fan is connected. The instructions with those systems MAY tell you how to adjust these settings, and you must do that to ensure the header uses the proper Mode so that the pump power supply from Pin #2 is correct. The Corsair H100i system, I suspect, does NOT do it this way. It has a direct connection to a good constant +12 VDC supply through its SATA source from the CPU and uses that for pump power, as well as for radiator fan power.

The Corsair H100i V2 system also has a FOURTH connection that OP has not mentioned. There is a cable to connect from a socket on the pump to a mobo USB2 port. In addition, you are instructed to download the free Corsair Link software utility and install it. THIS utility takes over all control of the H100i V2 cooling system - the system does NOT rely on the mobo controls for this. The Link utility communicates with the pump unit using that USB cable, and uses information from the mobo (especially the CPU chip's internal temperature) for its own methods of controlling the FANS on the radiator and monitoring for failures.

So, there are several ways that AIO cooling systems may be designed and controlled. Corsair uses one system in the H100i V2 product, and actually has used other systems in some of its other products. No matter whose system you buy, as OP says, it is IMPORTANT to read the instructions and follow them so that your system can do its job as designed.

Thank you for the information. Maybe I'll install my H100i Pro RGB next week.

 

[Paperdoc]

Let us know how it goes.

 

[ivictori]

Thank you for your advice however i would prefer to stay with the pump rgb header
Because we need to have assurity that the cpu fan header provides same amount of voltage power
I guess it doesnt because pump moves through water which is more power

Cpu fan mobes through air clearly not as much powerful

So better to leave it there