Advice on rejigging custom loop in Lian Li O11 dynamic XL

[Volemic]

Hi all,

 

I was hoping someone can provide some advice on what to do with my current o11 dynamic XL set up.

 

A bit of a background on this build - put it together start of 2020 and have upgraded a few things since (namely swapping a 2070 super for a 3090). Since the beginning, I've had terrible issues with heat... namely when I'm sitting next to the case, it feels like a Sauna, and if I touch the top of the case, I would say it's at least 60 degrees. CPU temps are generally terrible... on idle 45-50 degrees, full load coming up to mid-80s.

 

Current set up (Photo attached):

Lian Li O11 dynamic XL.

 - EKWB 360mm XE RAD bottom (3 corsair LL120 fans attached to this in exhaust setup)

 - EKWB 360mm PE RAD top (3 corsair LL120 fans attached to this in exhaust setup)

 - 1 LL120 fan attached to rear in exhaust set up

 - EKWB LianLi waterblock (hence no space for side fans)

 - GFX card water-cooled, CPU water-cooled, 12/16mm soft tubing throughout

 - 3.2DDC PWM EKWB pump

CPU: AMD Threadripper 3960x (I've turned off PBO, and even voltage limiting at the moment)

GFX: MSI Gaming trio 3090 (EKWB waterblock)

A few NVME drives

Seasonic 1050W snow silent PSU

 

The LL120 fans are terribly noisy, so I don't like going much over 30% ~700-900 RPM, and I keep the pump running at ~36% (noise)

 

This is what I'm in the processing of doing...

 

Add 3 Noctua AF120x15cm fans below the bottom radiator in intake setup, replace the bottom 3 LL120 fans with 3 QL120 fans and invert these to intake setup, change the rear fan to a QL120 in exhaust setup

 

Essentially this will mean bottom rad (thick) will be intake, top rad will be exhaust and rear fan will be exhaust. One alternative to this would be to add the noctua fans to the bottom rad, and keep this as an exhaust, keep the top rad as an exhaust and rely on the sole rear case fan as an intake

 

What's everyone's opinion on the most optimal set up?

 

PS. the temp reading of 35 degrees in the photo is immediately post cold boot! Also I intend on straightening up the soft tubing when I next dismantle the loop :D... looked better previously!

 

Any help is much appreciated!

 

 

[Stahlmann]

First off, it looks like all your fans are set as exhaust, which likely is one of the reasons why you need loud fans for proper cooling. I'd go for bottom and top intake, rear exhaust in your case.

 

If noise is a concern that it was the wrong choice to go with thick rads to begin with. I'm pretty much using the same loop layout in my O11D. But i'm using a 360 slim rad with NF-A12x25 fans as intake on the bottom and the same setup as exhaust on the top. If you plan on running low-rpm, a slimmer radiator will result in better temps than a thicker one. If you don't want to change out your rads, go for push/pull. Thick rads have much more resistance than slimmer ones and will need much more airflow (so basically more noise) to reach the higher cooling potential.

 

Also, the QL fans are pretty much the same as the LL series. So if you want to reduce noise, they won't make a difference. In fact they're even slightly worse on radiators. So you'll likely have them running louder to have the same cooling.

[Volemic]

Thanks for the feedback

 

In the (updated setup), I will put 3x Noctua NF-A12x15 below the thick radiator at the bottom and 3x QL120s above the radiator, I'm hoping that with this setup, I can still run at low RPM to get the air moving through. The spec sheet on the QL120 shows lower noise rating than the LL120... I have the white LL120 and max db rating is around 36db whereas max db on QL120 is 26 (probably because the QLs max out at 1500RPM, whereas the White LL120s max out at 2200)

 

The main benefit to having the QLs though is that I will be able to use them as intakes and still get good aesthetics. The LLs don't look great in the intake position.

 

You mention an interesting setup in having 2 intakes (at top and bottom) with an exhaust at the rear.... would this not result in very hot internals as the air is effectively traversing the hot radiator into the case?

 

I guess based on the fact that hot air rises, maybe its a better idea to intake at bottom and rear with the top exhausting

 

 

[Stahlmann]

7 hours ago, Volemic said:

The spec sheet on the QL120 shows lower noise rating than the LL120... I have the white LL120 and max db rating is around 36db whereas max db on QL120 is 26 (probably because the QLs max out at 1500RPM, whereas the White LL120s max out at 2200)

That's Like you said, the noise difference in the specs is because of the different max rpm alone. But if they're at the same RPM they will be the same noise mostly. They use the same rotor and motor in the end so the difference from the frame is only marginal.

 

7 hours ago, Volemic said:

You mention an interesting setup in having 2 intakes (at top and bottom) with an exhaust at the rear.... would this not result in very hot internals as the air is effectively traversing the hot radiator into the case?

That's the only way to get actual use out of your rear fan. Also if you have 6 intake fans you'll have positive pressure. The air will mostly find it's way out through pressure alone. Heavy positive pressure can work very well, but all fans as exhaust is just bad. Many cases, like for example the P400A Digital comes with 3 intake fans and no exhaust fan and it works extremely well. With this setup you would intake only fresh cold air through the radiators and the single exhaust fans combined with the positive pressure will move the air out of the back of your case.

 

7 hours ago, Volemic said:

I guess based on the fact that hot air rises, maybe its a better idea to intake at bottom and rear with the top exhausting

Yes, hot air will rise on it's own. But as soon as you get even a little airflow, it's already stronger than the natural rise of heat, So basically in a computer case with fans, this doesn't apply.