Question Be Quiet Silent Loop AIO problem -- PLEASE HELP :(

[Aaron_103]

I've recently built a new PC and having a problem with the Be Quiet Silent Loop AIO -- it's super frustrating! Possibly the case fans as well.

This is the first time I've installed an AIO so bear with me.

I believe I've installed the cables from the AIO into the right slots with the 3 pin AIO pump connector in the AIO pump slot on the mobo, and connected the 3 fans (as it's a 360mm cooler) into the 4 pin connector which slots into the CPU FAN header on the mobo.

Here's where it gets weird (or I'm being stupid). The AIO works and stays cool if I plug the pump cable (3 pin connector) into the CPU FAN header on the mobo, with the 3 AIO fans being connected in the back of the Lian Li case where the fan hub is, but it doesn't work if I plug it into the AIO cable into the AIO PUMP on the mobo (which is where it should go). When I boot with the 3 pin AIO cable in the AIO PUMP slot on the mobo, it doesn't make it past the bios as the CPU runs too hot (around 80 before shutting down). However, all the fans are spinning and the RGB lights are on.

If I leave the 3 pin AIO pump coming from the AIO in the CPU FAN header on the mobo (I'm surprised this even works?!) it works fine. But then I'm unable to control the fan speeds with the fans running at full speed. My fans are VERY loud and I can hear them from other rooms.

I'm not sure if I've explained this well enough, and I do apologise if I haven't. Please can someone help? Thank you.

Specs:
Ryzen 7900x3d
ROG Strix B650e-e
Kingston Fury 32gb RAM
Lian Li 216 Case
Nvidia 2060 (not new)

 

[Paperdoc]

I do NOT see this covered in the manual for the AIO system, nor in the manual for the mobo. But it's a common issue. You are right to connect the PUMP to the AIO_PUMP header, and the rad fans to the CPU_FAN header.

The PUMP unit of the AIO system is wired just like an older 3-pin fan. A quirk of the s design of new 4-pin fan system is that if you plug a 3-pin fan into a 4-pin fan header that IS using the new PWM Mode of control, that fan will run full speed all the time. This is exactly what that PUMP in your system needs. But to ensure that it works, the pump header MUST be set to use that PWM Mode.

The problem with today's common mobo fan headers is that they often come with a feature called AUTO Configure for the header MODE setting, and that's the default setting. In this mode, at every start-up it tests whatever is plugged in there to see if its speed can be controlled by a PWM signal. If not, then it changes to the older 3-pin fan Voltage Control Mode to be sure it CAN reduce the "fan" speed by reducing the Voltage supplied. That is exactly the WRONG way for your PUMP. So what you need to do with the AIO_PUMP header you are using is to go to that configuration screen and set this option to PWM, not Auto or Voltage or DC. Remember to back out to Main Menu and go through the Exit Menu to SAVE and reboot. This will provide full 12 VDC power to the pump at all times so it always runs full speed as intended,
Control of cooling of your CPU chip is done solely by changing the RAD FAN speeds via the CPU_FAN header operating in PWM Mode.

 

[Aaron_103]

Firstly, just wanna say thank you for taking the time to respond.

If I've understood you correctly, I've changed the QFAN settings in the bios for the CPU FAN and AIO PUMP to PWM mode. Is this correct?

Once changed, then insert the AIO PUMP cable into the AIO PUMP header on the Mobo, and the rad fans into the 4 pin connector which goes into the CPU FAN header on the Mobo.

Is this right?

 

[Paperdoc]

Yes, that is right. Let us know how that works.

 

[Aaron_103]

I gave this a try whilst waiting for your reply and sadly it doesn't work.

When I boot into BIOS my CPU temp increases to over 80 degrees extremely fast, within about 10-20 seconds.

It's almost like the CPU cooler isn't cooling the CPU, but, the fans are spinning and RGB works fine too.

If I plug the AIO PUMP cable coming from the cooler into the CPU FAN or CPU OPT header it works and cools fine, but why not in the AIO PUMP header? Very confused.

 

[Paperdoc]

I could not find a mobo manual with clear descriptions of the options on its fan headers. So here's my version of "typical" options and correct settings for the AIO_PUMP header in your situation.

1. Profile: "Normal" or "Standard", not Turbo or Max or Quiet or Manual or Custom, etc. Let it try to use the default means of deciding what fan speed to use.
2. MODE: Set to PWM Mode, not Auto or DC or Voltage. This setting is how the control signals are sent out to achieve the speed that Profile has decided.
3. Temperature Sensor: IF you have a choice, set to the CPU temperature sensor, not another on the mobo.

NOTE: I see in the manual p. 1-9 that, among the several fan headers, ONLY the AIO_PUMP header is specified as "Full Speed" and that it can NOT be accessed or controlled through the Q-Fan utility. You may need to try to find it in BIOS Setup - see the manual, p. 3-2 for how to get there. In my experience, you do NOT just tap the "Del" key at re-boot. You should hold it down until the opening screen of Setup shows. Then look for fan headers and see if you can find that AIO_PUMP header to check its settings.

The way the manual reads, one would expect that the AIO_PUMP header already does what it must - keep the Voltage on Pin #2 at +12 VDC always. But in case it does not, you can use another way. First, plug the PUMP into the CPU_FAN header, and configure that as above - especially setting to PWM Mode. This will ensure the pump gets a constant 12 VDC supply from Pin #2 and runs full speed all the time. ALSO that header will monitor the PUMP speed signal for possible FAILURE. In a AIO system, the item most critical to check for failure is the pump - no circulation = NO heat removal! Then plug your RAD FANS group into the CPU_OPT header. That header is a copy of CPU_FAN, so it WILL adjust your 4-pin rad fans to keep the CPU temperature under control.

 

[Aaron_103]

Thanks for all your advice so far. I checked off your first three points and can confirm bios settings were set to PWM and CPU temp sensor.

Referring the holding 'del' key, I wasn't sure what you meant here? I tried to do this when you enter the bios screen but nothing happened. Would you mind giving me some further context please?

I tried plugging the rad fans into CPU FAN and OPT FAN Mobo slots with the AIO plugged into the AIO PUMP Mobo slot but temps rise to an unsafe level and comp shuts down.

When I plug the AIO cable and rad fans into the CPU fan and OPT fan slots it works fine. The problem seems to be with the AIO PUMP Mobo slot or pump itself. I'm curious to hear your thoughts on this and if you believe this to be a pump or Mobo issue?

This is my first build in 5 years and I've never used an AIO before. The fan(s) seem really too loud to me, it sounds like if you were running a fan on a hot summers day to keep you cool at mid to high level. Is this normal?

What I might do is return this pump and purchase another one if I can't fix this in the next day or two.

 

[Paperdoc]

You say, "When I plug the AIO cable and rad fans into the CPU fan and OPT fan slots it works fine." So it all works when connected to fan headers we already know ARE working properly. This STRONGLY indicates that your problem was that the AIO_PUMP fan header is faulty and never did provide adequate power to your pump. Going forwards, I recommend you leave things connected this way. The CPU_FAN header does provide proper power to the pump as long as it is set to PWM Mode. Further, it does monitor the speed signal from the pump for possible failure. The CPU_OPT header will also provide the same type of voltage and signals when in PWM Mode, BUT the 4-pin rad fans you plug in there WILL use the PWM signal to control their speeds.

You do say something odd. "The fan(s) seem really too loud to me..." I would NOT expect those rad fans to be running full speed most of the time. Do you mean they are STILL noisy and fast when the pump is powered properly via the CPU_FAN header? Or was that only earlier when the pump was not working and the system overheated? If they are running really fast now when the Pump is working and the system does NOT overheat, post back here for ideas on how to address that.

Regarding entering BIOS Setup. Normal instructions are to reboot and hit the "Del" key to enter. Two points to clarify that.
1. During the early part of the POST process the system will look for such a keypress and NOT complete the full boot-up. Instead it will go to the opening screen of BIOS Setup. BUT if you push that key too late (when the POST process is almost complete), it will not "see" that and will finish booting, This can happen very quickly, especially if you have an SSD to boot from. So you must do the push VERY quickly after starting the reboot. If you do not get into Setup, try the process again.

2. If you merely tap the "Del" key in that time frame, sometimes the POST process is so "busy" it fails to "see" that and does not process it properly. That is why I suggest you do not merely tap - hold the "Del" key down until the opening screen of Setup appears.

 

[Aaron_103]

I've managed to fix the loud fan issue. Luckily I found a video from Lian Li on YT which demonstrated how to properly set up the case. They missed an important part of the video, and someone commented with the fix. Basically, the case fan hub has a FAN1 slot that needs to be connected to the mobo. I had it connected to a different slot on the case fan hub, and this fixed the loud noise issue (it was the case fans, not the AIO).

It seems as though my issues are fixed apart from the AIO_PUMP problem. As you say, this will likely be a mobo issue as it's likely not providing adequate power to the AIO.

My last question is -- should I contact ASUS & Be Quiet to troubleshoot the problem and possibly get a replacement?

Or, do you think it is fine to leave it as is, with the cables connected to the CPU_FAN & CPU_OPT connectors?

My concern is either the AIO or mobo failing as the AIO pump is in the 'wrong' slot, and longevity as these parts are not cheap. I don't plan on changing for at least another 3+ years if all goes well.

 

[Paperdoc]

Probably simpler to leave the pump connected to CPU_FAN, and rad fans to CPU_OPT. There is NO difference between this and having the fan in AIO_PUMP. As designed (apparently not as it mis-performs currently) that header is the SAME as the CPU_FAN header in many ways, but it simply never tries to reduce the speed of whatever is plugged in. The CPU_FAN header certainly DOES monitor the item connected there for failure. If it detects failure, it will pop up a warning on screen plus (as most do) may actually shut down your whole system within a short time without even waiting for the CPU temperature reading to go very high. This is a preventive action to avoid sudden high CPU temp that might damage it with no heat removal. As I said, the speed of the rad fans connected to CPU_OPT WILL be controlled according to CPU internal temperature.