Pump changing speed

[arconz]

I've had a new system build with an Asus Dark Hero motherboard and an EK D5 pump for a custom loop. 2 420mm rads cooling just a CPU at this stage (5950X), so kinda overkill surface area lol.

When I first got the rig they had set the pump to run at 100% constantly which was very loud at 4.8K rpm and totally unnecessary I think. Thing is when I set it to PWM with a temp curve in BIOS, it appears to change speed randomly even when the CPU is not really doing anything... this pump makes a fluttering sound whenever it changes speed so I want to avoid this if possible.

What are the temp curves others are using with a D5 and/or what is the best way to avoid frequent speed changes? Do I have something set incorrectly in BIOS? Thanks in advance.

 

[Hudzy]

Ideally you would have a temperature sensor for the water in the loop somewhere, and set a temp curve using that sensor.

It sounds like it's set to the CPU temperature at the moment, which spikes a lot for half a second at a time.

 

[SirConfused]

With pumps you don't really need to ramp speed up/down with temp at all. As long as the pump is pushing fluid round at a reasonable rate, the temps will equilibriate across all the components. Set the pump to a reasonable rate (probably something quite low given you're only cooling the CPU on a massive amount of rad) that makes minimal noise/vibration while still flowing and you'll be fine.

 

[LuckyBenski]

^^ what these guys said. Constant speed is fine for a pump and ideally you can just set it somewhere you're happy with the noise level and leave it.

If you do want it to react, it should react to liquid temp (this is true for fan speed too actually). I used a temperature sensor in a G¼ plug connected to an Aquaero Farbwerk. This lets me have LED colours change according to loop temperature, but also I can feed in that temp data to other apps.

 

[arconz]

Ideally you would have a temperature sensor for the water in the loop somewhere, and set a temp curve using that sensor.

It sounds like it's set to the CPU temperature at the moment, which spikes a lot for half a second at a time.

Ah... this is the problem, its set to CPU temp. Setting a constant speed for the pump is fine but it would be cool to have water temps as an option - so basically they will have to drain the loop to install sensors lol?

This is the store that is doing the assembly, would I need two of these parts? What would be the optimal locations for them in the loop? The Dark Hero has water in & out headers. My rads are EK Coolstream which have only dual ports, and my res is a D5 Heatkiller 200 using the default in-out ports. I have the multi-port top for it but they didn't install this.

 

[Hudzy]

You should only need one of those sensor parts, as the water temperature should be equal throughout the whole system, give or take a degree. I fitted mine to an unused inlet on the pump.

 

[arconz]

You should only need one of those sensor parts, as the water temperature should be equal throughout the whole system, give or take a degree. I fitted mine to an unused inlet on the pump.

This is the EK pump I have.. its just a motor which attaches underneath the Hetkilller res. Would I have to install the multiport res top to get an extra inlet? Either that or remove that motor and install an EK pump which has a spare inlet, like the Quantum Inertia? Seems like the expensive option though lol.

Also should it attach to W_IN or OUT on the motherboard, doesn't matter?

 

[Haz123]

Stop and think because you answer the problem in your own question.

Do not use a fan curve at all with a pump. Set it to a static flow rate like 50% with no variation and do not alter it at all. If you are happy with the noise and temps then leave it. If you want less noise then reduce the pump speed and monitor temps. If tempt to high then put pump speed up but still leave it to a static value

Do not over complicate the situation and create a problem that does not exist. The problem is the fluttering speed when it changes rpm so then just set it at a set flow rate so no variation. If you need to control the temps and do not want to alter the pump then alter the fan speeds. It is a balance between pump speeds and fan speeds.

Remove the variables and simplify the problem.

 

[arconz]

If you need to control the temps and do not want to alter the pump then alter the fan speeds. It is a balance between pump speeds and fan speeds.

Yup that makes sense & I understand I don't need water temp info, but it would be cool to have the option (and it can also drive RGB lol).

Using no pump curve - assuming you wanted to keep the rad fans at the same speed - is it likely you would need a higher static speed than if you used a curve that was say 75% flat then had an increase for high fluid temp?

 

[Haz123]

You have to experiment. The laws of thermodynamics wil not change because you want them too.

"!s it likely you would need a higher static speed than if you used a curve that was say 75% flat then had an increase for high fluid temp?" ---- Stop over complicating. You have a working loop so make minor adjustments as you need. Find the pump flow rate you like and stick with it. If temps are ok and not too loud then enjoy.

 

[Grim5]

I've had a new system build with an Asus Dark Hero motherboard and an EK D5 pump for a custom loop. 2 420mm rads cooling just a CPU at this stage (5950X), so kinda overkill surface area lol.

When I first got the rig they had set the pump to run at 100% constantly which was very loud at 4.8K rpm and totally unnecessary I think. Thing is when I set it to PWM with a temp curve in BIOS, it appears to change speed randomly even when the CPU is not really doing anything... this pump makes a fluttering sound whenever it changes speed so I want to avoid this if possible.

What are the temp curves others are using with a D5 and/or what is the best way to avoid frequent speed changes? Do I have something set incorrectly in BIOS? Thanks in advance.

Never set the pump speed to cpu temp lol

actually never set anything to the cpu temp

 

[SirConfused]

Careful about linking to competitors. The first one you linked doesn't ship outside NZ, but the second one does, which will be against the rules.

Something else to consider before you go out and buy new things is if your mobo actually supports a temp input/has an appropriate header. If it's this board then it looks like the answer is yes, but you didn't state the exact model so I can't be sure.

 

[arconz]

Find the pump flow rate you like and stick with it. If temps are ok and not too loud then enjoy.

Is this done by manually making the PWM Qfan curve "flat" or is there another setting where I can set a specific speed? (The rig is currently in the shop & I can't remember BIOS options).

 

[Grim5]

Is this done by manually making the PWM Qfan curve "flat" or is there another setting where I can set a specific speed? (The rig is currently in the shop & I can't remember BIOS options).

you can set the pump rpm in the fan controller menu, well that's how I do mine on my asus pump. You can also set the pump rpm using software like Argus monitor.

There isn't really any good reason for the pump to run at max speed or to have its speed change all the time - a fixed speed is best

 

[arconz]

I have the PC back and its working great with the pump set at 50%. I have the option to use water temp as I got the sensor installed anyway - it will be interesting to keep track of the fluid temp over the seasons [currently winter] and in different usage scenarios. Now at 22°C, that's with all 8 140mm fans silent at 900rpm

 

[Combine Harvester]

I have the PC back and its working great with the pump set at 50%. I have the option to use water temp as I got the sensor installed anyway - it will be interesting to keep track of the fluid temp over the seasons [currently winter] and in different usage scenarios. Now at 22°C, that's with all 8 140mm fans silent at 900rpm

It's good that you have the sensor anyway as loop temp is the best and most efficient way to control fan speeds. Fluid never goes up or down to quickly, so will not ramp up/down your fans constantly as CPU temp would and it also gives you a true representation of your loops efficiency compered against ambient temp. Pump best set on constant RPM, or as mine on two steps: 0-35°C - 800RPM(20%), so it can keep 6°C over ambient with fans on 500RPM when CPU and GPU is idle browsing net, or watching Netflix and 36°C+ - 3600RPM(70%), so it keeps 12°C over ambient with 1200RPM fans when under load when gaming and such.