ROG Strix LC III 360 ARG AIO What should the pump speed be?

[Orodruin]

Hello everyone;

I'm using Asus ROG Strix LC III 360 ARGB Liquid Cooling with my 7900X3D processor and ROG Strix B650E-E motherboard.

I was previously using the 1st generation of this model. And when using it, I always used it in DC mode and at full speed with the Pump speed setting.

Now, in this new model, the Pump speed technical document states that it operates in the range of 800-2800RPM. And when I do Calibration from the motherboard's QFAN menu, it manually configures the pump speed to operate between 2600 and 2800. There are also Silent/Normal/Turbo options.

What adjustment do you recommend I make for the pump speed? Many people recommend using a Constant speed on the internet. Some people also say that using the processor at full speed when it is not under load is unnecessary and will shorten the working life of the pump.

What do you think is the best setting for me to make?
I would be very happy if you could give me information about this.

 

[pressing on]

Your motherboard has an AIO Pump Header, connect the pump to that and it will run at full speed all the time. The benefit of varying pump speeds is unclear, some people report it only makes a few degrees difference in CPU temps.

The main controller of CPU temps is the AIO fans and to a lesser degree the case fans. Its easier to set a profile for them based on 100% pump speed because its a constant factor and the fans are tied only to how hot the CPU is. Varying the pump speed could mean the fans running faster because the pump is running slower.

 

[cvaldes]

I've diddled around with different AIO pump speeds on several builds using several AIOs and in the end, I came to the conclusion (which has been published by others) that AIO pump speed does not affect cooling performance as much as fan speed & type (given the same radiator).

I also did this with several custom cooling loops with the same basic results. Coolant flow velocity is less important than radiator/fan performance.

If there's an extra motherboard header I will set the AIO pump to function at 50% (6V) at idle and run at 100% (12V) on a full CPU load. If there is no extra header, I'll just let it run at 100% and move on with my life.

 

[Orodruin]

Your motherboard has an AIO Pump Header, connect the pump to that and it will run at full speed all the time. The benefit of varying pump speeds is unclear, some people report it only makes a few degrees difference in CPU temps.

The main controller of CPU temps is the AIO fans and to a lesser degree the case fans. Its easier to set a profile for them based on 100% pump speed because its a constant factor and the fans are tied only to how hot the CPU is. Varying the pump speed could mean the fans running faster because the pump is running slower.

I'm using it the way you already said. The pump is connected to the AIO_Pump socket on the motherboard. However, the pump automatically adjusts the speed to variable mode (PWM Mode), not fixed (DC Mode).

In other words, it does not run at a constant speed like other AIO coolers. The technical specifications of the product also state that it operates between 800-2800RPM.

That's why I wanted to ask, is it a problem if this turnover rate is variable? Or should I set it to a constant speed and use it?

I've diddled around with different AIO pump speeds on several builds using several AIOs and in the end, I came to the conclusion (which has been published by others) that AIO pump speed does not affect cooling performance as much as fan speed & type (given the same radiator).

I also did this with several custom cooling loops with the same basic results. Coolant flow velocity is less important than radiator/fan performance.

If there's an extra motherboard header I will set the AIO pump to function at 50% (6V) at idle and run at 100% (12V) on a full CPU load. If there is no extra header, I'll just let it run at 100% and move on with my life.

Then, from your comment, I come to the following conclusion;

It does not matter if the pump speed of the product in my hand is variable. I should use it as is, right?
Because its operating range is between 800-2800rpm. and it adjusts automatically.

I don't need to set it to a constant speed then, right?

 

[cvaldes]

If your AIO pump is automatically changing speeds by itself I'd leave it alone. It sounds like Asus engineers programmed it to do what I have to set manually in the BIOS.

Good for Asus. Good for you, you can move on with your life.