Can the pump in Liquid Freezer II be inaudible at low rpms and still cool sufficiently?

[NewbieOne]

Arctic Liquid Freezer II owners, can you hear your pumps in idle or low loads or can they be kept below room ambient?

 

I know the thing can run cooler and quieter than D15 under high loads, but it still being water and having a pump, I'm specifically concerned about it's ability to remain silent in idle and not be louder than air coolers under low loads.

 

According to what I saw in one test, the fans kinda ranged from 25 to 35 dbA while the pump produced a flat 29 dbA, which wasn't a problem under high loads but wasn't ideal under low loads either. So how's this in practice?

 

 

[Tristerin]

Your pump speed determines the speed at which water is passed across the block (which pulls the heat away from the block) so absolutely does affect thermals.  If there was an idle mode (not doing anything) your block would superheat quite quickly btw.  

 

Id say if you can hear your pump that much even at full blast - you have air trapped in it.

[Deli]

In low load and idle, how much power the CPU use? Even with reduce pump speed, say 85% of max speed. Why can't the AIO keep CPU temperature under control?

 

You can set a custom pump curve in BIOS, just like fan curve.

[NewbieOne]

6 minutes ago, Tristerin said:

Your pump speed determines the speed at which water is passed across the block (which pulls the heat away from the block) so absolutely does affect thermals.  If there was an idle mode (not doing anything) your block would superheat quite quickly btw.  

 

Id say if you can hear your pump that much even at full blast - you have air trapped in it.

Yeah, I know you can't go into passive mode like with the beefiest air coolers — the pump has to always be working, however fast or slow.

 

I also know you can't hear it that much, at least on the Liquid Freezer II.

 

My problem is if you can hear it at all from under your desk in a quiet room at night when working in MS Office. Essentially, if the pump has a quiet mode in which you don't hear it at all but it still manages to cool your CPU well enough in idle/low loads.

 

3 minutes ago, Deli said:

In low load and idle, how much power the CPU use? Even with reduce pump speed, say 85% of max speed. Why can't the AIO keep CPU temperature under control?

You can set a custom pump curve in BIOS, just like fan curve.

 

Yeah, I know, it's just that — will the pump on the Freezer still provide sufficient cooling if you reduce its speed to inaudible levels?

 

Darn, they should make water blocks with heatsinks on/under them.

 

[Deli]

12 minutes ago, NewbieOne said:

Yeah, I know, it's just that — will the pump on the Freezer still provide sufficient cooling if you reduce its speed to inaudible levels?

 

Darn, they should make water blocks with heatsinks on/under them.

 

I bet yes. In idle and low load, the CPU draws very little power. Just a bit of water flow to the CPU water block will be enough to keep the CPU cool. Indeed I set mine with an Alpha DC-LT pump at 85% when the CPU is less than 55C. This way the pump is quiet enough, even a Noctua A12x25 at 600rpm is loud enough to cover the pump noise. If you know how quiet the A12x25 at 600rpm is.

And the idle temp of my R5 3600 is 32C.

[Tristerin]

3 minutes ago, NewbieOne said:

Yeah, I know you can't go into passive mode like with the beefiest air coolers — the pump has to always be working, however fast or slow.

 

I also know you can't hear it that much, at least on the Liquid Freezer II.

 

My problem is if you can hear it at all from under your desk in a quiet room at night when working in MS Office. Essentially, if the pump has a quiet mode in which you don't hear it at all but it still manages to cool your CPU well enough in idle/low loads.

 

 

Yeah, I know, it's just that — will the pump on the Freezer still provide sufficient cooling if you reduce its speed to inaudible levels?

 

Darn, they should make water blocks with heatsinks on/under them.

 

Depends on the CPU.  If its as good as a D15 then I would assume with no overclock you could leave it on quiet mode if there is a software (like iCUE) available or you could manually adjust the pump header in BIOS.  So I cant specifically answer your question as I have no use case with their user interface. IF you can adjust, and the CPU isn't a volcano, you should easily be able to run it in "quite" mode with low RPM on the fans

 

If you can do that, you should achieve what you need (no volcano chip, no crazy high ambient temps in your work area)

 

As for the waterblock, that is the heat sink.  The radiator is the surface area for dissipating that heat.

[NewbieOne]

3 minutes ago, Deli said:

I bet yes. In idle and low load, the CPU draws very little power. Just a bit of water flow to the CPU water block will be enough to keep the CPU cool. Indeed I set mine with an Alpha DC-LT pump at 85% when the CPU is less than 55C. This way the pump is quiet enough, even a Noctua A12x25 at 600rpm is loud enough to cover the pump noise. If you know how quiet the A12x25 at 600rpm is.

And the idle temp of my R5 3600 is 32C.

Ummm… A12x25 is a bit out of my league financially, or at least has been until recently, so I have no experience, but I'd be surprised if I could hear it at all, except maye in a noisy situation like pulling through a filter. On a CPU or as unfiltered exhaust I suppose 600 rpm on A12x25 would be totally inaudible?

 

4 minutes ago, Tristerin said:

Depends on the CPU.  If its as good as a D15 then I would assume with no overclock you could leave it on quiet mode if there is a software (like iCUE) available or you could manually adjust the pump header in BIOS.  So I cant specifically answer your question as I have no use case with their user interface. IF you can adjust, and the CPU isn't a volcano, you should easily be able to run it in "quite" mode with low RPM on the fans

 

If you can do that, you should achieve what you need (no volcano chip, no crazy high ambient temps in your work area)

 

As for the waterblock, that is the heat sink.  The radiator is the surface area for dissipating that heat.

Yeah, I know the basics. Was just joking that having both a traditional huge heatsink and a rad with water pipes would be ideal for temps/noise balance. Don't mind me if my ignorance of physics showed (as it does from time to time).

 

I would ideally keep the fans and the pump each just under the audible level most of the time, then allowing them incrementally more rpms as needed. Once audible fan speeds already became inevitable, I would also allow the pump to hit the same level. Between the pump and the fans, the exact curve would have to be figured out by experimentation. But what I worry about is whether — as opposed to the fans, which you can — you can keep the pump completely inaudible without overheating.

[Deli]

1 hour ago, NewbieOne said:

Ummm… A12x25 is a bit out of my league financially, or at least has been until recently, so I have no experience, but I'd be surprised if I could hear it at all, except maye in a noisy situation like pulling through a filter. On a CPU or as unfiltered exhaust I suppose 600 rpm on A12x25 would be totally inaudible?

You can still hear it if you stick your ears two inches from it.

[Deli]

3 minutes ago, NewbieOne said:

 

I would ideally keep the fans and the pump each just under the audible level most of the time, then allowing them incrementally more rpms as needed. Once audible fan speeds already became inevitable, I would also allow the pump to hit the same level. Between the pump and the fans, the exact curve would have to be figured out by experimentation. But what I worry about is whether — as opposed to the fans, which you can — you can keep the pump completely inaudible without overheating.

You get it.

[Tristerin]

35 minutes ago, NewbieOne said:

But what I worry about is whether — as opposed to the fans, which you can — you can keep the pump completely inaudible without overheating.

Depending (no use case experience here) on the pump it will have a bare minimum speed before it wont work at all (not enough voltage) so once you find that (unless software available to do it for you) you should be able to achieve what you want (even a BIOS "fan" curve on the pump header perhaps)

[BTGbullseye]

On 9/20/2020 at 8:04 AM, NewbieOne said:

Arctic Liquid Freezer II owners, can you hear your pumps in idle or low loads or can they be kept below room ambient?

Having even a single P12 fan running at minimum functional speed (about the 20% mark) is louder than the pump at maximum speed, as long as there's no air in the pump.

[NewbieOne]

15 hours ago, BTGbullseye said:

Having even a single P12 fan running at minimum functional speed (about the 20% mark) is louder than the pump at maximum speed, as long as there's no air in the pump.

That'd be 320–350-ish rpm? I'm pretty sure that's inaudible even to me, unless pulling or pushing through the rad and the case filters amplifies the acoustics.

 

I really did the way Freezer II is quieter than D15 for the same temps under high loads on high OCs, just want to make sure silent idle is also possible.

[BTGbullseye]

17 hours ago, NewbieOne said:

That'd be 320–350-ish rpm? I'm pretty sure that's inaudible even to me, unless pulling or pushing through the rad and the case filters amplifies the acoustics.

 

I really did the way Freezer II is quieter than D15 for the same temps under high loads on high OCs, just want to make sure silent idle is also possible.

Yeah, those RPMs are accurate. (as is the quiet)

 

Honestly, I've never heard mine at all in testing. The fan on my X570 is way louder than the pump, and the P12's at full speed are just barely louder than that.