Will I notice a difference in temps if I upgrade my fans?

[Xdm29]

Hi all, I am on a custom watercooling loop with 13900k and two Corsair 360mm radiators, XR5 and XR7. I made the mistake of buying the older ML120 PRO RGB fans.

I don't think the current fans have enough static pressure/airflow to dissipate the heat from the radiators as I can reach up to 46c coolant temp and 70-80c CPU temp in Battlefield V.

Will I see a temp decrease if I change to the ML120 Elite RGB fans? Since it has higher CFM, static pressure with the air vanes and all?

Thanks

Edited January 24 by Xdm29

[c-attack]

6 hours ago, Xdm29 said:

Will I see a temp decrease if I change to the ML120 Elite RGB fans?

No, there will be no noticeable performance change. Be careful with static pressure values. They are typically listed at the maximum speed of the fan and that is not usually the speed at issue. If Fan A has a 3.0 mm rating at 2000 rpm and fan B has 2.75 mm value at 1800, it doesn’t tell you anything about what you get at 1200 rpm from either fan. In the above example both fans are likely to have similar performance. The ML Pro and ML Elite have the same fan blade. They are going to have similar performance. The only reason to change would be for RGB lighting (4 vs 8 LEDs). Even between a very good radiator fan and a bad one, the difference in temp on a multi radiator system might be 1-2C. The more radiator surface area, the less fan choice matters and you can use lesser performers with minimal cost. There are extremely high FPI test radiators that are meant to be used with fans speeds of 1800 rpm plus. The XR7 and XR5 are not like that and work well at a range of speeds by design. 
 

If your system is running at 46C coolant temp, the least likely reason is the inability of the fan to push air through the radiator — other than if you are keeping the speed pinned down at 700-800 rpm. If you are using the Hydro X presets, you may prefer something that ramps up the speed sooner and it a more linear fashion rather than the late surge at high temps. 
 

For most users higher than expected coolant temp is going to be about the environment. If your gpu is air cooled, then that is going to be a factor. If the inside case air temp is 46C, then liquid temp also will be 46 regardless of cpu load. The other thing users may run into is when the front radiator dumps its heat into the top radiator. Combine that with gpu heat pouring into the top radiator and you are directly heating your coolant and thus cpu as well. We probably need to talk about how your system is laid out. 

[LeDoyen]

A photo would help a lot.

Knowing what case it is too. some have pretty terrible airflow. If you add to that the typical front intake + top exhaust as C-attack said, that introduces even more losses in efficiency. Aircooled GPU in the case and it's doom for your water temps ^^'.

When i was waiting for my GPU waterblock, running it aircooled with only the CPU on 3 radiators, i had pretty bad temperatures, just because of the amount of heat in the case dumped by the card.

[Xdm29]

Hi guys, yes I do have an aircooled GPU. 

Case is Lian Li O11 XL, 6 ML120 Pro RGB fans in total. The top XR5 rad is set as exhaust while the bottom XR7 rad is set as intake. CPU and mobo is cooled using a monoblock. Using a side distro plate as well so I do not have the option for a side rad. 

Ambien temps are 24c. Coolant is 37-38c at idle.

Perhaps it is wiser for me to spend the money on a waterblock instead of changing my fans...

Edited January 24 by Xdm29

[LeDoyen]

the top rad is taking the heat of the bottom rad plus the GPU.. it's the only radiator working with 24°C air to cool the water. the top rad is trying to cool water with whatever air temperature is inside the case.

With an aircooled GPU, it's a bit of "choose your poison". You could run both rads as intake and be done with the GPU heating the loop, but the case and the GPU will become hotter.

Both as exhaust may work (with the back fan set as intake), but you dump GPU heat on both rads now. Still it may be better..

 

with everything watercooled, all exhaust with back intake will keep the case cooler, and you can remove the bottom dust filter too since it wouldn't be needed anymore, increasing airflow.

[c-attack]

LeDoyen and I are both O11 owners, but that is not a configuration I have run or tested before.  If you do both top/bottom as intake, you will need a strong fan in the rear as you attempt to blow it all out the back fan and mesh.  You might get better cool air in with top/bottom as dual exhaust, but I suspect that won't last once the GPU heats up and you'll be back to where you are now.  The dual exhaust will be the best choice if you can get the GPU on a water block.  That really is the big mover here and likely takes 20C off every temperature in the case from CPU to RAM to chipset and on.  

[Xdm29]

20c is insane. I will try to get my GPU underwater but the waterblock I want is almost never in stock lol. So top + bottom will be exhaust, rear will be intake. Should I get a high rpm fan for the rear intake?

[LeDoyen]

even a high speed fan won't provide as much airflow as 6 exhaust fans 😉 and the O11 rear end is vented enough to have plenty of air coming in.

On mine i did remove all the PCIE brackets and made a magnetic bracket with some fine stainless steel mesh as dust filter, and mounted a Noctua 90mm fan to it to blow fresh air to the bottom radiator. If you like DIY that can be an option too, i gained a little degree on water temp with that thing 😛

you can just run the loop as is when you'll have the GPU block, and see if you need to tweak afterwards. it's always better to change one thing at a time to see what the results are.

The top rad will always be the hottest since it's the first in line, so this one benefits the most from the rear intake of fresh air. the rest is fine tuning, to taste.

[Xdm29]

Ok, I'll just add things one at a time. Thanks guys, appreciate the informative responses.

[c-attack]

2 hours ago, Xdm29 said:

 

20c is insane. I will try to get my GPU underwater but the waterblock I want is almost never in stock lol. So top + bottom will be exhaust, rear will be intake. Should I get a high rpm fan for the rear intake?

 

I don’t think you need the rear fan at all if running both top/bottom as exhaust. The design of the mesh on the rear slot makes that a noisy fan regardless and I never liked anything back there. I’d say you only need it if running both rads as intake and I would certainly do some on/off comparisons to see if it helps. 
 

With the gpu in the loop, that’s 300-600W that is no longer being dumped into the case. Instead it gets pumped and blown out top/bottom. So while your liquid temp increases from heat being added, the case temp drops an enormous amount more than offsetting the gain. Internal air temp reductions benefit everything in the case and it’s likely your current situation is directly related to the internal air temp.