[SOLVED] How to best utilize 3 fan headers for fans and AIO pump

Feb 7, 2021
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Greetings! My mITX motherboard (ASUS Z170i Pro Gaming) has three fan headers only: CPU_FAN, CHA_1 & CHA_2. I plan on using a Y-Splitter to connect both Kraken X53 radiator fans to the CPU_FAN header and utilizing PWM. For the remaining two fan headers (CHA_1 & CHA_2), I will be connecting three case fans and the AIO pump. Two of these case fans are 120mm 3-pin , and one is a 92mm PWM. The pump is a 3-pin connector.

Specifically, I am uncertain as to whether it is okay to connect the AIO pump to a Y-Splitter, as opposed to connecting it directly into the motherboard header. As the pump has a 3-pin connector, does this mean it will run at 100% speed even if connected to a PWM Y-Splitter along with a PWM fan that is using a custom speed? I understand that the pump should run at 100% constantly.

The Noctua 92mm is blowing directly onto the GPU, and therefore I would like for this fan to be PWM performing accoring to GPU temp, if possible.

Your recommendations and support will be very much appreciated.
 

Paperdoc

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And the last shall come first....
The problem with your plan is that there never has been any way for a GRAPHICS CARD to send to the mobo a GPU chip temperature, so that the MOBO can use that to control a fan aimed at the card. So that Noctua fan aimed that way can have its speed controlled a couple of ways.
(a) Connect it as you plan, to a CHA_FAN header, and configure that header to use PWM Mode of control and the MB (motherboard) temperature sensor. That is NOT the temperature inside the GPU chip by any means, but it does reflect the air temperature in the case.
(b) Connect the same, but set that header to use the CPU chip temperature sensor, betting the heat generation due to workload changes in the CPU chip will be VERY similar to heat generation and workload in the GPU chip.
(c) Forget control of this fan. Just set it to run full speed all the time, by powering it directly from the PSU with an adapter cable. This does NOT make any use of its PWM capability. It may over-supply air to the graphics card, but that does no harm.
(d) Connect as in (c) above, BUT look what came with the Noctua fan. SOME of their fans come with little items they call "LNA" for Low Noise Adapter. This is used when your fan is connected to a full 12 VDC power supply and has no speed control. It simply inserts into the fan power supply connector and is a resistor to reduce the fan speed (and airflow, and noise).
You have not told us details of your graphics card. Most actually have their own cooling fan built in, and most of those do their own fan speed control based on their GPU chip's internal temperature. They just cannot send those signals back out to the mobo for use there.

Your thoughts about powering the pump and fans of the Kraken X53 system are on the right path. The PUMP part is wired just like a 3-pin fan. Any 3-pin fan (and this pump) plugged into a 4-pin mobo header that is using PWM Mode for control (and your mobo's CPU_FAN header DOES do it that way) will always operate at full speed all the time. That IS what your pump is supposed to do. So I recommend that you get a simple 3-output 4-pin fan SPLITTER like this

https://www.amazon.com/Splitter-Computer-Extension-Converter-TeamProfitcom/dp/B07F8LV1BY/ref=sr_1_4?crid=1B5YJ1RA6HC0W&dchild=1&keywords=fan+splitter+4+pin&qid=1612756562&sprefix=fan+splitter,aps,183&sr=8-4

and plug that into your CPU_FAN header. Look closely at the three output arms. Only ONE of them has all four of its pins, and that is the only one that will send back to the CPU_FAN header the speed of its device. So plug into that one the 3-hole cable from your PUMP, then plug the two rad fans into the other outputs. The CPU_FAN header has an important second function: it monitors its device's speed signal for FAILURE. If that happens it will alert you immediately, and SOME mobos may take quick action to shut everything down even before the CPU internal temperature sensor shows high temps. In an AIO system, the critical component to monitor for failure is the pump. As long as it runs, even with partial rad fan failure, you get CPU cooling.

If you connect this way, the PUMP will run full speed all the time as designed and its signal will be monitored for failure. The RAD FANS both WILL be controlled for speed by the PWM Mode of the header, but that header will never "see" nor display those fans' speeds. From time to time YOU should verify they both still work.

So that leaves your two front 3-pin case fans to connect. If you are already using one CHA_FAN header for the Noctua aimed at the graphics card, connect them both to the other header using a Splitter. (Yes, you can use a 4-pin Splitter for this.) If not, you can connect each to its own separate header. In either case, since these are 3-pin fans, ensure that they are configured to use DC Mode and to use the MB temperature sensor.
 

Paperdoc

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And the last shall come first....
The problem with your plan is that there never has been any way for a GRAPHICS CARD to send to the mobo a GPU chip temperature, so that the MOBO can use that to control a fan aimed at the card. So that Noctua fan aimed that way can have its speed controlled a couple of ways.
(a) Connect it as you plan, to a CHA_FAN header, and configure that header to use PWM Mode of control and the MB (motherboard) temperature sensor. That is NOT the temperature inside the GPU chip by any means, but it does reflect the air temperature in the case.
(b) Connect the same, but set that header to use the CPU chip temperature sensor, betting the heat generation due to workload changes in the CPU chip will be VERY similar to heat generation and workload in the GPU chip.
(c) Forget control of this fan. Just set it to run full speed all the time, by powering it directly from the PSU with an adapter cable. This does NOT make any use of its PWM capability. It may over-supply air to the graphics card, but that does no harm.
(d) Connect as in (c) above, BUT look what came with the Noctua fan. SOME of their fans come with little items they call "LNA" for Low Noise Adapter. This is used when your fan is connected to a full 12 VDC power supply and has no speed control. It simply inserts into the fan power supply connector and is a resistor to reduce the fan speed (and airflow, and noise).
You have not told us details of your graphics card. Most actually have their own cooling fan built in, and most of those do their own fan speed control based on their GPU chip's internal temperature. They just cannot send those signals back out to the mobo for use there.

Your thoughts about powering the pump and fans of the Kraken X53 system are on the right path. The PUMP part is wired just like a 3-pin fan. Any 3-pin fan (and this pump) plugged into a 4-pin mobo header that is using PWM Mode for control (and your mobo's CPU_FAN header DOES do it that way) will always operate at full speed all the time. That IS what your pump is supposed to do. So I recommend that you get a simple 3-output 4-pin fan SPLITTER like this

https://www.amazon.com/Splitter-Computer-Extension-Converter-TeamProfitcom/dp/B07F8LV1BY/ref=sr_1_4?crid=1B5YJ1RA6HC0W&dchild=1&keywords=fan+splitter+4+pin&qid=1612756562&sprefix=fan+splitter,aps,183&sr=8-4

and plug that into your CPU_FAN header. Look closely at the three output arms. Only ONE of them has all four of its pins, and that is the only one that will send back to the CPU_FAN header the speed of its device. So plug into that one the 3-hole cable from your PUMP, then plug the two rad fans into the other outputs. The CPU_FAN header has an important second function: it monitors its device's speed signal for FAILURE. If that happens it will alert you immediately, and SOME mobos may take quick action to shut everything down even before the CPU internal temperature sensor shows high temps. In an AIO system, the critical component to monitor for failure is the pump. As long as it runs, even with partial rad fan failure, you get CPU cooling.

If you connect this way, the PUMP will run full speed all the time as designed and its signal will be monitored for failure. The RAD FANS both WILL be controlled for speed by the PWM Mode of the header, but that header will never "see" nor display those fans' speeds. From time to time YOU should verify they both still work.

So that leaves your two front 3-pin case fans to connect. If you are already using one CHA_FAN header for the Noctua aimed at the graphics card, connect them both to the other header using a Splitter. (Yes, you can use a 4-pin Splitter for this.) If not, you can connect each to its own separate header. In either case, since these are 3-pin fans, ensure that they are configured to use DC Mode and to use the MB temperature sensor.
 
Feb 7, 2021
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Paperdoc; your reply is greatly appreciated.

The graphics card for this build is an R9 Nano, and chassis an NZXT H210. Due to the very close proximity of the GPU to the PSU shroud in this case, the 92mm Noctua fan is zip-tied under the PSU shroud and blowing directly onto the R9 Nano like in this video:
View: https://youtu.be/XQaAY9vHTKU?t=454
(I'm using an SFX power supply as well, of course).

An additional question that comes from this: With this 92mm fan running at 100% as you've suggested, do you foresee an issue with it blowing air directly into the GPU fan at such close proximity?

The 3-output 4-pin Splitter that you've suggested is conveniently included in-box with the Kraken X53! Is it okay to connect all three components (two 120mm PWM rad fans and the AIO pump) to this single motherboard header? The mobo manual states that the header supports a maximum of 1A fan power, and I believe the total amperage of these three components combined will be under 1A. With that said, does this not cause any strain on the mobo, especially considering that two of the fans are PWM?

Following your recommendation of using the 3-output Splitter, and if also using a Y-Splitter for the two case fans, this frees up the third header for the 92mm Noctua, thus allowing for PWM, if desired. You mentioned the LNA (Low Noice Adapter), which I hadn't heard of and is a great thing to know. Would you recommend running at 100% with the LNA, or using a custom fan speed with PWM?
 

Paperdoc

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Handy that you have the Splitters you need already. The specs for the Kraken X53 system show a max current load of pump plus both rad fans as 0.94 A, so that is OK on one header.

If you connect the Noctua to the second CHA_FAN header, do NOT use the LNA thing IF you even have it. Just use the header's controls on PWM Mode. You can set it to a fixed speed in BIOS Setup (and change that easily if you decide to), or set it to control speed automatically, perhaps using the CPU temp sensor on the assumption that workloads on both CPU and GPU are correlated. Given the layout of your parts, the temperature of the air inside the case (as measured by the mobo temp sensor) is pretty much irrelevant to graphics card cooling, since its air supply will be almost all from outside air drawn in by that Noctua fan.
 
Feb 7, 2021
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A quick update—I received the following advice from NZXT and curious to know others' thoughts:

It's generally not recommended to connect both the pump and the fans to the same header. We would recommend having the fans connected to one of the CHA_FAN headers and then run the pump itself off the CPU_FAN. This makes sure that the pump is only supplying TACH information to the motherboard while the fans are safely handled from the CHA_FAN header. Adding all of these to the same header is not a great idea, as the fans will not be able to be controlled properly if chained with the pump sense cable.

Per the advice above, my understanding is that component connected to the 4-pin connector of the 3-way splitter will supply the TACH information. Is it true that the fans will not be able to be controlled properly if chained with the pump to the same header?
 

Karadjgne

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The problem with your plan is that there never has been any way for a GRAPHICS CARD to send to the mobo a GPU chip temperature, so that the MOBO can use that to control a fan aimed at the card.
SpeedFan can do that. Simple as changing the addressing as to which sensor controls which header. Can set all fans to respond to gpu temps if you wish. Can even change a sys_fan header to respond to cpu temp, or the cpu_fan header to respond to motherboard temps.

There's 2 ways to install a basic aio. Nzxt/corsair and pretty much everybody instructs that the pump go to cpu_fan and fans go to sys_fan. That's to cover their posterior since it's assumed that the pump will fail before the fans do. The cpu has a built in safety check, if cpu_fan is not populated or falls below a set threshold, the cpu shuts down/refuses to boot. So if the pump fails, pc is protected. That works great, except the sys_fan sensor is not the cpu temp, but the motherboard temp somewhere else, and rarely ever sees over 40-50°C. So your fans are not controlled by cpu temps. Sucks for gaming.

The other method is what most ppl do, against recommended instructions, and install the aio fans to cpu_fan header and the pump to a sys_fan. Cam controls the pump by the reported tach, Cam controls the fans according to cpu temp. Everything works as it should. When you game, cpu temps climb, so does the fan rpm.

Take your pick, neither way is wrong, one way just works better, the other has a better sense of security.

Cam controls pump speeds by the usb, the tach wire is just the reporting tool. The pump will climb as high as 4000rpm in some series, fans do not. Pwm works on a % scale, not a temp scale, so when a sensor reports a specific temp, Cam fan curves say to move the header pwm pulse to x% , but that may not be what Cam wants the pump to change to. Having 1 tach means only 1 % change, not 2.

There's also other factors, like startup amperage is not running amperage, fans can and do spike (listen to an air conditioning compressor, same thing at start) amperages. So that 0.9A total, isn't, it can be considerably higher, which can burn out a header. Also not all headers are the same. It's generally accepted that a header is 1A at 12v. In reality there's motherboards (cheap ones) that may only max out at 0.9A. So those 2 fans added with the pump is really pushing your luck when the cpu is hitting high loads.
 
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Paperdoc

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I do disagree with what NZXT said. A fan header does NOT need the fan speed signal to be able to control that speed. In fact, it never uses that info for that function. It uses a speed signal for only two things: to display it for you for info and interest (not critical); and to monitor it for fan FAILURE. Furthermore, when you use a Splitter, only ONE fan's speed can be reported to the header, so that failure monitoring can only check ONE fan. YOU still have to do your own checks of the other fan(s). Hence, having NO rad fan speeds fed to the mobo header means only that YOU have to check BOTH of them for failure, not just one. NO difference there! Plus, you can't "see" those speeds if you are curious.

Secondly, the details of how failure monitoring is done differ from one mobo to another, and they never tell you those details in the manuals! But in general, the CPU_FAN header in particular (and likely any AIO_PUMP header if you have one) does much more that just sending you a screen notice when failure is detected (by lack of a speed signal). On some mobos after a relatively short wait, the system may actually shut down your system to prevent CPU overheating without waiting for the CPU's internal temp sensor to report excess temperatures. It also MAY refuse to allow the system to boot if it gets no speed signal immediately on starting. Now, in an AIO system, the most important item to monitor for failure is the PUMP. Without that, no fluid flows to remove heat, so CPU overheating can happen rapidly. On the other hand, if ONE of the fans on the rad fans fails but the pump keeps going, there is SOME heat removal and the rise in internal CPU temperature is slow, so that the normal CPU temperature limits, including both CPU speed throttling and possible shut-down, can act quickly enough to deal with that. So, if you have to choose which component of an AIO system should be monitored very closely with rapid response available in the event of failure, between the PUMP and the RAD FANS, I say the PUMP is the one that should be monitored by the CPU_FAN header. So that is where you should connect the PUMP. IF you are using a Splitter for that and including other items (like rad fans) on that header, then you must ensure that the PUMP is the item whose speed is sent to that header by using the only Splitter output arm with ALL FOUR pins.

No matter which way one chooses that, it is IMPORTANT in the Kraken system (and others that use the mobo's built-in fan control systems) that the RAD FANS be controlled by a header that CAN use the CPU internal temperature sensor for guidance. Your mobo DOES allow you to make that choice in configuring any of its CHA_FAN headers, so for you it IS possible to connect the PUMP to the CPU_FAN header and the RAD FANS to a CHA_FAN header properly configured. Not all mobos have that option.

Karadjne raises a valid point on header load. Most headers can supply up to 1.0 A max current to the connected load. (I have seen a few that are less, and a few that are more.) Several threads earlier have commented that these header's hardware components CAN withstand a load higher than that for a short time, and that is sufficient to allow for start-up surge current with no damage to the header. However, that assurance is NOT guaranteed for any and all mobos, and you will never find any mention of that in a manual. So, for your mobo, OP, I said the max load is spec'd at 0.94 A, and that is acceptable. But maybe not - we cannot really know. If you are concerned about that, then your best option is to put only the PUMP on the CPU_FAN header, and use a Splitter to put the TWO rad fans on a CHA_FAN header configured to use the CPU temp sensor. That then means that your two front case fans will also need a Splitter to connect to the other available CHA_FAN header.
 

Karadjgne

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then your best option is to put only the PUMP on the CPU_FAN header, and use a Splitter to put the TWO rad fans on a CHA_FAN header configured to use the CPU temp sensor. That then means that your two front case fans will also need a Splitter to connect to the other available CHA_FAN header.
That's the best way to do it regardless.
MITX is a tiny box, even the larger optioned cases. CFM is cubic feet per minute and a single 120mm averages about 50cfm. A cubic foot is 1' x 1' x 1' and an mITX isn't close to those dimensions, considerably smaller overall. You'd be looking at a single intake and single exhaust fan effectively replacing the entire volume of air inside the case every 1 second, ±.

That's a ton of air movement. So setting equal fans at same rotation and cfm in pairs maximizes potential. Keep intakes as a pair, exhausts as a pair and pump on the last header.
 
Feb 7, 2021
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Paperdoc, as always, and Karadjgne, thank you for the informative responses. You guys are beasts.

At this point then, I'll probably opt for the consensus method which is to utilize the CPU_FAN header for the pump only, and use Y-Splitters to connect the remaining four fans (two and two) to CHA_FAN headers. That leaves the additional fan (92mm zip-tied under the PSU shroud) without a header. I'm thinking a good option, per Paperdoc's advice above, is to connect this guy directly to the power supply and use a Low Noise Adapter to preserve its lifespan as much as possible.

However, would it be viable to use a Y-splitter to connect both the pump and this 92mm fan to the CPU_FAN header (ensuring that the pump is occupying the 4-pin connector, of course)? This way, the pump provides TACH info to the mobo for fail-safe, and the 92mm fan can be controlled with PWM, as opposed to just running 100% if connected to the power supply.
 

Paperdoc

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I suggest a different arrangement. At the core of this is that the rear fan should really be controlled according to the temperature sensor on the mobo, NOT by the CPU chip's internal sensor.

The way you have things allocated right now is:
CPU_FAN header us solely for the PUMP of thre AIO system. It is set to PWM Mode and always uses the CPU temp sensor - that header has no choice on this latter item.

CHA_FAN 1(?) both rad fans via a 2-output Splitter, set for PWM Mode and using the CPU internal temp sensor for guidance, since it is for CPU cooling.

CHA_FAN2 (?) for two 3-pin case ventilation fans via a Splitter, set for Voltage Control Mode (aka DC Mode) and using the mobo temp sensor for guidance.

FIRST: check the ratings of those two 120mm 3-pin case vent fans. I expect their max current rating is less than 0.25 A each, but verify. Then check similarly the rating for that 92 mm rear fan; I expect also it is below 0.25 A.

SO, what I suggest (assuming the total load is under 1.0 A) is that you use a three-output Splitter to connect both of the two 3-pin 120 mm case fans AND the rear 92 mm fan to that second CHA_FAN header. This would put that rear fan under automatic control based on the mobo temp sensor. Now, that is a PWM style fan and Voltage Control Mode is not quite ideal for its control. However, it WILL work that way - that is part of the backwards compatibility features of this design. Among those three fans, it does not matter which of them is plugged into the only Splitter output that has all four pins.
 
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Feb 7, 2021
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Thank you for these points and suggestions.

The 92mm fan, however, is mounted under the PSU shroud (not the rear) bringing air up from the bottom vent of the case. In addition to circulating more air in general, I did this particularly to help cool the GPU which is otherwise mildly choked by its close proximity to the PSU shroud (which is perforated, of course, thank god).

Per my research, the max input current of the fans is a follows:
  • 120mm NZXT fan (AER F case model): 0.18A
  • 92mm Noctua NF-A9 PWM chromax.black: 0.1A
Based on this, it seems minimal risk to burning out the header, even considering start-up spike and fluctuations noted above.

Is there any major drawback to connecting the pump to the CPU_FAN header via Y-Splitter along with the 92mm Noctua (per Karadjgne's advice, ensuring the pump is connected to the TACH wire, of course)?
 

Karadjgne

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Electrically you are fine either way, we'll under amp ratings for any of the headers. The difference will be in response. Assuming decent fan curve settings, with that 92mm on a 3way splitter to case fans, it'll respond the same as the other case fans, spinning up/down with motherboard temps/case temps. If it's split from the pump, it'll use the pumps settings as per Cam. Almost universally, the pump (mostly nzxt uses variable speed pumps, many don't) will be activated by one of 2 settings (which you choose in Cam). It'll respond to coolant temp or cpu temp. Your choice. I prefer coolant temp as coolant takes far longer to saturate and change vs an erratic cpu under loads. Eliminates fans ramping up/down at idle or low loads with windows services startups.

So as long as you are electrically sound, you can do either way, or try both and see which makes better sense as thermals are a variable depending on case choice. See which has a better impact on gpu temps when gaming longer than 20-30 minutes, does that affect noise outputs, etc.

There's very few times ppl can claim absolutely that any setup is wrong, if things work as intended. My case has almost zero defined airflow, I've seen ppl use the rear and top as intakes (BTX especially), my old case I didn't use a rear exhaust at all since the 280mm worth of fans on top created a chimney affect with an aio. The nzxt H500-H510 series benefits considerably by not using intakes at all. The Silverstone Ravens don't have any exhaust fans yet are highest ranked airflow cases. So there's no perfect answer, no absolute yes or no you did it wrong, unless you do something completely insane like have all intakes or all exhausts or mount the tower backwards to case airflow.

You'll figure out what works best for you as to which placement and connection, as long as you stay well within electrical parameters for the header.
 
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Feb 7, 2021
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Finally completed this build per the fan setup suggested above (AIO pump on CPU_FAN; DC case fans on CHA_1; and PWM radiator fans on CHA_2) and entered Q-Fan Control in the BIOS for the first time.

Unlike the other two headers, CPU_FAN (AIO pump) does not offer a selection between PWM and DC. @Paperdoc, you suggested above that the AIO pump should be set to PWM—is there a way of confirming that this header is running PWM? Also, the default setting for this header is "Standard." Should I change it to "Full Speed?" I know it has previously been recommended to run the AIO pump at max speed, but I'm curious as to why Full Speed would be preferable over Standard, or if it would even make a difference since the pump is a 3-pin connection? On Standard, the pump averages 880–890 RPM. I assume this will climb drastically under load—is this normal? Would the "Full Speed" setting change any of this?

Apologies for the noob questions. First time tampering with custom fan setups.. Thanks again, as always.

 

Karadjgne

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There's 2 kinds of Aio pumps. Fixed speed and variable speed. By far the most common is fixed. This is because there pumps are such low flow and the tubing is small diameter internally that it's not a good idea to run them at anything less than flat out. Some few companies, like nzxt and Swiftech have actually put some R&D into their pumps, they are still Asetek or Coolit based, but they are not a factory specd pump. This, combined with software, allows the pump to run at slower speeds if the pumping action isn't required. That extends the life of the pump. It gets to run at its own idle. The speed is determined by an algorithm in combination with cpu and coolant temps. Basically when cpu loads and temps climb, the software tells the pump 'let's go to work', and when coolant temps drop, 'take a break'.

A Standard fan curve is more aggressive than a Silent fan curve, the fans spin up faster, sooner. By setting a 3wire pump to pwm, the fan curve won't matter or make any changes, it gets a constant 12v, max power. The pump doesn't have a pwm signal wire to change the speeds. If the pump is 4wire, it'll be a variable speed pump, and while it can be regulated, it depends on from where. My loop has a thermal coupling, so I can control the pump from either coolant temps or cpu temps via Asus FanXpert. Variable speed pumps designed around software like iCue or Cam, have something similar.

With motherboards, only the cpu_fan header is guaranteed to be default pwm, so set on pwm or auto, it'll act as pwm. Any other header is varied, some can be pwm default or DC default, it varies. So leaving set as Auto, you've no idea of the actual control of a pump on a sys_fan header, which can be bad if it's DC and starts cutting voltage to the pump, treating a full speed pump as a variable speed pump. Cooling ability at low loads goes in the toilet. Too little flow.

So it's usually best with a fixed speed, 3 wire pump, just to set the header on pwm and avoid DC voltage changes altogether. If the header doesn't change to pwm, just set the minimum duty cycle to 100%.
 

Paperdoc

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THIS POST MAY BE WRONG! PLEASE SEE MY NEXT POST.

As I recall, you are using a Kraken X53 AIO system and their CAM software. Regarding the PUMP speed (connected to the CPU_FAN header) it should operate at max speed all the time. However, I do NOT know for sure whether the CAM software changes that. SOME AIO systems with this control system DO allow the software tool to change the pump speed. When doing that, it is not a continuous smooth change according to recent small temperature changes - such a strategy would cause interference with that type of control applied to the RAD FANS. Instead, the pump speed MAY be changed in a "range set" scheme that has the pump run at a lower speed for very low temperatures, or change to a high speed when temps are high, but not change frequently. As I said, CAM MAY do this, or may NOT.

The speed you report for that pump seem very low to me. Further, I am surprised that there appears to be no place to alter the MODE of the CPU_FAN header, as shown in your screen shots. The mobo manual says that the BIOS Setup configuration options allow such a setting. However, there IS a way to get around that, and you've got your eye on it. My recommendation above was to plug that pump cable into the CPU_FAN header and then set the header to PWM Mode. This uses a quirk of the design of a 3-pin fan (or pump) system. When the header IS using the new PWM Mode, the 3-pin connection does NOT allow the PWM signal to affect anything, so the pump's speed is totally fixed by the Voltage supplied from Pin #2. In PWM Mode that is always + 12 VDC, so it runs full speed and effectively ignores whatever the header it trying to do on speed control via the PWM signal. BUT if the header is NOT doing it that way - IF it is using the older Voltage Control Mode - then the pump's speed WILL be altered constantly by the VARYING Voltage from Pin #2. So certainly one way to prevent that is to set the fan header's PROFILE to Full Speed. In that Profile it does not matter what the measured temperatures are, or which MODE the header is using. Irrespective of those options, Pin #2 will always supply the full +12 VDC power, and the pump WILL run full speed.

So, OP, make that change. Observe the pump speed displayed before and after the change. I expect its speed will be much faster, proving that the header previously had been in Standard Profile and using Voltage Control Mode, not PWM Mode. If that is what happens, leave it this new way.
 
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Paperdoc

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In the post above I completely lost track of the impact of CAM. Most software of that type takes over control of the AIO system components to control CPU cooling, and does not leave any details to the mobo CPU_FAN tools. I do NOT know how NZXT's CAM does this in detail, and I can't find a manual for that software. I also don't know what tool your screen shots show. I appears to be a tool from the mobo maker, ASUS, but I am confused by its lack of a MODE setting option.

The Kraken X53 system has a power feed directly to the pump unit, and a connection to a USB2 header so CAM can communicate with that. Thus it is POSSIBLE that CAM is controlling power to the pump (and hence its speed), and settings you make in BIOS Setup (or using an ASUS utility app) may NOT change what the pump does. IF that is what is going on, when you make the change to Full Speed in BIOS Setup, it may NOT actually change the pump speed. If that happens, it would suggest that CAM is the actual control point here. In that case, look through the CAM software configuration tool screens to see if there is any mention of that. I am NOT suggesting that you change what CAM is doing, if anything. You might also ask NZXT Tech Support about that detail. BUT if the changes DO work and make your pump run full speed, than ignore this warning, and just proceed with the advice from my previous post.
 
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Thank you, both. I am using the ASUS UEFI BIOS Utility and upon entering advanced mode I've found some additional settings such as Q-Fan Source which offers the option of setting the fan header to go by CPU or motherboard temps (@Karadjgne, you noted that this can also be set using SpeedFan). This section also confirms that CPU_FAN is set to PWM Control. @Paperdoc, when you say "alter the MODE," are you referring to the Q-Fan Source?

I have also installed NZXT CAM whereby the Fan Speed of the pump displays 1841 RPM. Subsequently, I checked the ASUS BIOS and the CPU_FAN now displays 1841 RPM as well, as opposed to 880 RPM previously. @Paperdoc, to your point above about NZXT CAM potentially taking precedence in control over the pump, I think that's probably what is going on here.

@Karadjgne, you previously noted that the pump can be set to respond to either coolant temp or cpu temp in CAM, however I do not see this option and per some quick research, it seems that Kraken X*3 series AIOs no longer offer this option (and thus automatically go by cpu temp). I could be wrong, though.

Per the lower-right screenshot, CAM also offers various settings for the pump: Silent, Performance, Custom, Fixed. "Silent" is the default setting. I assume it's a matter of trial-and-error monitoring temps while gaming to determine the optimal setting?

 

Paperdoc

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In BIOS Setup for the CPU_FAN header (see mobo manual p. 2-35) there are basically only two items. The CPU Q-Fan Control offers the choice of DISabled (no control) or PWM Mode (automatic pre-configured control). It does NOT have any option for using the older Voltage Control Mode. so set that to PWM Mode.

Once you do that you have the options to set the CPU Fan Profile. Standard will use the pre-set "fan curve" settings of what speed to run for what measured temperature. Silent will run at a fixed slow speed for low noise and significantly reduced cooling that is NOT adjusted according to temp. Turbo is fixed full speed at all times - that may be what you want to choose for your case. Manual uses automatic speed control, but allows you to specify the "fan curve" it uses. Note that this header does not offer a choice of temperature sensor, it always uses the one inside the CPU chip.

Since this header uses only PWM Mode, the actual choice of Profile should not matter, since the connection of the 3-pin pump cable to the header does not allow any speed control.

Note that a choice of Q-Fan Source (which temp sensor to use) is offered ONLY on the CHA_FAN headers. That allows you to re-purpose one of those IF you need to to respond to CPU temperatures, whereas the "normal" way to guide a case ventilation fan is from the motherboard sensor.

Your post indicates that, prior to this, you were NOT using CAM. In that case the CPU_FAN header could have been set to anything, and the CAM software was doing nothing. It is also possible that the default speed of the pump when it receives NO signal from CAM is very slow just to get you going. But anyway, it is clear that CAM DOES allow you to make a few choices of PUMP speed as well as controlling the rad fan speeds. In that strategy, your choice should be guided by how fast the rad fans are having to run, which will depend on workload. For this purpose, note the difference in your screen shot between the Fan Speed you have marked in a red rectangle, and the Kraken X3 Pump Speed below that. CAM CAN tell you those two items separately and is doing so. I am sure the Fan Speed is the RAD FAN speed. By the way, the means by which CAM can "read"the Pump speed is that that signal is being fed to the CPU_FAN header by the 3-pin cable plugged in there. So you will see the SAME Pump Speed reading from CAM and for the CPU_FAN header (except that the CPU_FAN header will call this the "Fan Speed").

The four choices you listed for the Pump Speed Profile highlighted with the red oval VERY likely are: "Silent" = fixed reduced speed for quiet operation but requiring faster fan speeds; "Performance" = faster pump speed for higher workloads which allows the rad fans to operate more slowly at moderate workloads, but will still be able to raise the rad fan speeds to handle high workloads; "Custom" to allow you to create some non-standard setting; and "Fixed" which, I suspect, allows you to specify the fan speed. Note that this system makes it possible to change pump speeds to get your rad fan speeds into a comfortable range, but is not intended for frequent pump speed changes. The actual minute-by-minute adjustment of rad fan speed according to the CPU temp sensor is how this automatic system controls CPU cooling. Note the Pump Speed and rad fan speed, then change the Pump Speed setting to Performance. You should see its reported speed increase a fair amount, and a slow reduction in rad fan speeds for no change of workload.

Now, go back up to the chooser box labelled "Cooling", showing "Default" as the current choice. I suspect THAT is where you select what CAM uses for its selection of automatic rad fan speed control "fan curve". Examine what other choices it has - probably similar to what BIOS Setup would offer for the CPU_FAN Profile. "Default" is probably a good place to start.

As you anticipate, once you're used to how CAM works, you can monitor workloads and temps and pump and rad fan speeds, and decide when to call up CAM to alter the Pump Speed.
 
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Karadjgne

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Cam puts your coolant temp (liquid) as 23°C. It'll offer the option for cpu or liquid on another page, usually when you get to the actual pump curve settings.

I used Cam for years with my X61, set for Silent and just let it be. The difference between Silent and Performance was @ upto 4°C at max, 0°C at idle and a marked gain in fan speeds per temp setting, resulting in some serious gains in noise. Overall I was hitting 70°C in Prime95 with Silent, gaming was 55°C, so the extra 3-4°C really wasn't worth the effort. Silent really was very quiet, 600rpm-700rpm averages.
 
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Silent pump it is then. Thanks for sharing those figures, @Karadjgne. Also, I will gladly take the L on my note above about Kraken X*3 no longer supporting liquid monitoring as per your prediction I did find that setting in CAM (bottom-right screen below). That was very helpful.

@Paperdoc, indeed it looks like CAM is monitoring radiator fan speed ("Fan Speed") in addition to the pump. What confuses me here is that in the BIOS Utility, CPU_FAN (AIO pump connection) is displaying a speed that matches CAM's "Fan Speed" monitor. Then, CHA2_FAN (where the radiator fans are truly connected on the motherboard) is showing 736 RPM. I have this header set to PWM Mode so 736 RPM seems far more accurate for idle speeds than 1829 RPM. My question then is if pump is operating at 1869 RPM (per the screenshot of CAM below) and the radiator fans are spinning at 736 RPM (per ASUS BIOS), what is operating at 1829 RPM?

Another question: Regarding the three case fans set to DC (CHA1_FAN), @Paperdoc you mentioned in your original post to set these fans to use the motherboard temperature sensor (which I have now done). My understanding is that since these fans lack the 4th PWM pin and therefore can only run at a single speed (unless the voltage is modified directly), what does setting these fans to go by MB temperature sensor do? Will the BIOS utility adjust the voltage of these fans so that they speed up and slow down according to motherboard temperature?

 

Paperdoc

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Who knows what? Which is true? Those are puzzling but important questions.

Start with this: Both BIOS Setup and CAM do NOT know how you have positioned the fans in your case. The each know only the speed signals being received at the headers according to the mobo labels on them. But CAM has one other piece of info that BIOS does not - we'll get to that.

What is plugged into your CPU_FAN header? The PUMP. But BIOS Setup calls that the CPU FAN, because that's what it was intended for. And then CAM picks up a speed at that header and ALSO calls it the CPU FAN speed for the same reason. Moreover, it is getting the value from the BIOS.

What is plugged into the CHA_FAN2 header? You say it is the two RAD FANS. BIOS Setup merely calls them CHA2 FAN, and CAM does not even report them - they are supposed to be CASE fans on that header that CAM does not work on. I presume you have configured this header to use the CPU temperature sensor for its guide, since these fans really are your CPU cooling system. Remember that, although CAM reports this speed, it is NOT controlling those fans. Control is being done by the BIOS.

What is plugged into CHA_FAN1? I presume a CASE ventilation fan running about 1683 RPM. That is what BIOS Setup says, and again, CAM does not report that - it's just another case fan.

Now, CAM also reports a different number for the PUMP SPEED at 1869 RPM, so where does that come from? Well, there is a USB2 cable connection from the PUMP to the mobo for CAM to use as its communication link. It appears that CAM gets the real PUMP speed signal - the SAME one that the CPU_FAN header is receiving - and does its own counting job on that, to yield its own "version" of the speed. And the answer is slightly different. I believe that's just calibration differences between the ways that the two devices (BIOS and CAM) are processing the pulses they receive.

Regarding those actual CASE ventilation fans on CHA_FAN1 - you say they are 3-pin fans. IF you leave the header configured to PWM Mode, they will always run full speed, despite what you tell it to use for the Profile. BUT look at your mobo manual p. 2-36. For the CHA_FAN1 header only (the ONLY one of these two that is using 3-pin fans) the very first item "Chassis Fan 1 Q-Fan Control" should be set to DC Mode. This will allow the header to DO speed control of those fans according to mobo temperature.
 
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