[SOLVED] AIO Pump RPM?

[Jing__]

I have a masterliquid ML360 and I have the pump plugged into my CPU_OPT and my 3 fans plugged into CPU_FAN.

I'm quite confused about CPU fan curves and would like to know why I can use the BIOS to change the fan curve for the RPM of my CPU_OPT when it's just a pump. Is it changing how fast my pump is working or something?

 

[tennis2]

You want your pump to run at 100% all the time. Set that accordingly.

 

[CountMike]

I have a masterliquid ML360 and I have the pump plugged into my CPU_OPT and my 3 fans plugged into CPU_FAN.

I'm quite confused about CPU fan curves and would like to know why I can use the BIOS to change the fan curve for the RPM of my CPU_OPT when it's just a pump. Is it changing how fast my pump is working or something?

CPU_FAN and CPU_OPT are on same controller but different motors would send confusing signal to controller giving you wrong info and speeds. They are meant to use with identical fans.
On that particular cooler, pump is meant to run full speed all the time. If your MB has AiO_Pump header, connect pump there, if not on any other header where is possible to set manually to max speed.

 

[Paperdoc]

Actually, I would recommend that you plug the AIO pump into that CPU_OPT header. Then be sure to set it to use fixed max speed at all times. Why that particular header? To some extent, I'm just hoping for something here. You have not told us what mobo you have, but most mobo manuals do not disclose what I'm looking for anyway. On all mobos, the CPU_FAN header pays special attention to the fan speed signal at that header for detection of FAILURE of the CPU fan. So even if that is really a PUMP on the CPU, failure detection of the pump is just as important. Now in your case, the recommendation is to plug the rad FANS into the CPU_FAN header so their speeds are governed by that header, using the CPU chip's internal temperature sensor for guidance. The PUMP should be on the CPU_OPT header set to max speed. I am hoping that the mobo actually does monitor the CPU_OPT header speed signal for failure, just as it does on the CPU_FAN header.

Now, to be sure of failure monitoring, you could reverse that. Put the AIO Pump on the CPU_FAN header and set it for fixed max speed, and it WILL be monitored for pump FAILURE there. In an AIO system, pump failure is the most critical item for failure monitoring. Then connect the rad fans to the CPU_OPT header and set it to its normal automatic fan control, ensuring IF there's a choice that it uses the CPU internal temp sensor, and not one on the mobo. Most CPU_OPT headers can do this just fine. It is the dedicated PUMP headers on some mobos that cannot control the speeds of their devices. IF the CPU_OPT header does monitor its load for fan failure, that's good; if it does not, other CPU overheating protection systems will be sufficient even if one or both rad fans fail, as long as the pump is still working..

 

[Paperdoc]

To whomever down-voted my post (above) of Apr8/20, you are RIGHT. That three-year-old advice is WRONG! Sorry!

The Correct plan is this. Plug the PUMP into the CPU_FAN header. Plug the RAD FANS into the CPU_OPT header. You have not told us what mobo you have, but the following is common for most mobos. The CPU_FAN and CPU_OPT headers are pretty much identical, and you can only configure the two of them the SAME. Go into the CPU_FAN header and ensure that that is set to the Normal or Standard PROFILE so that it will use it default automatic fan speed control system that is guided by the temperature sensor inside the CPU chip. Also ensure that the header MODE setting is set to PWM Mode, and not to Voltage or DC or Automatic. You can check to be sure that the CPU_OPT header has the SAME configuration, but I expect you will NOT find a separate screen for it. When done, use Esc back to Main Menu, then F10 to get to the Exit Menu. There choose to SAVE and EXIT to save these settings and reboot.

Why? The PUMP is wired just like an older 3-pin fan. So, when you connect it to a header using the new 4-pin PWM Mode, it will always run full speed,. That is exactly what that pump is designed to do! The CPU_FAN header will monitor the speed signal it gets back from the PUMP pluigged into it for NO speed signal indicating FAILURE, and give you a biog warning if that happens. Meanwhile, the 4-pin RAD FANS connected to the CPU_OPT header WILL have their speed controlled by the PWM signal they get.

 

[Karadjgne]

The motherboard only sees a motor plugged in. It has zero capability of any kind of determination as to what that motor is or does. In pwm motors, the cpu assigns a % of rpm to start, according to the curve and current temp. When the temp goes up, so does the curve, so that % is increased to match. Actual rpm is meaningless, to the motherboard, as such. So 50% pwm could be 500 rpm with a 1000rpm fan or 2000rpm with a 4000rpm AIO.

Same affect with a DC / 3pin motor, but the % is a voltage instead, generally ranging from 5v-12v.

When you change the curve, you change the %/volts per °C, no different to flat-lining the curve at 100%, you are setting 100%\12v for every °C