Switching fans for a corsair h100i v2 AiO, temperature difference

[Tempas]

Hi guys, I bought a H100i v2 recently and stock fans for it seem loud. I'm looking to switch them out. From my reading, I found the fans I think I'm going to settle with but I can't seem to find much about temperature differences for them. The fans I chose are Noctua NF-F12, and so,

TLDR : How will the NF-F12s perform in relation to the stock fans, temperature wise ?
If much worse, any recommendations which would perform similarly but would be quieter ?

I'm also open to other fan suggestions. Many thanks to anyone who responds!

Also... my current temps on prime95(with AVX) are ~70C and without AVX are ~60C. For anyone interested.

 

[devbiker]

The more relevant temp to measure your fan performance is the coolant temp. And it's not likely that the NF-F12s will provide any better cooling for the coolant than the stock fans. That said, a 737 on takeoff is quieter than those fans so you'll likely see a pleasant difference in noise.

Personally, I swapped my stock fans out for ML-120s and was quiet happy with the performance and noise level. With the MLs, anything over 1600 RPM was literally unnecessary - the cooling performance wasn't any different.

 

[Paperdoc]

At maximum speed, the Noctua units will deliver significantly more airflow at much lower noise levels. So it is VERY likely that they actually will run a little slower and much quieter than the SP120L fans that came with your H100i system.

Unless there is something wrong with your system now, you will not likely see a temperature change. Why, if the fans are better? Well, the automatic control system involved in the H100i is a TEMPERATURE control system. That is, it manipulates the fans' speeds however is necessary to meet the target it has for the Temperature inside the CPU chip. That target is part of the default settings in the H100i system for your CPU type. As long as the current fans are sufficient and can do their jobs without reaching maximum speed, that system IS meeting its temperature target. So, when you change the fans, it will simply adjust them to whatever speed it takes to achieve the SAME temperature target. IF you decide that target is not right you probably have the option in the Corsair software that controls the H100i system to create a custom temperature target - fan speed curve, but that may not be necessary if the CPU already is operating at reasonable temperatures. VERY likely, though, you will see much lower noise levels even with no other changes made by you.

 

[Tempas]

Thanks for your responses guys! Yeah I didn't expect the new fans to outperform the stock fans, in fact the opposite. I expected them to do a bit worse but I am willing to take the hit. You seem to think they'll do about the same which is really comforting though! Another question is, what's the main difference between the corsair ML-120 and NF-F12 fans ? From my research the noctuas are just quieter but push a little less air. Is that pretty much it ?

 

[devbiker]

Both fans are excellent choices for radiators. The ML fans, particularly, use a magnetic levitation bearing - it "floats" - so there is little to no friction on the bearing and no bearing noise. They should also last for a very long time.

 

[Paperdoc]

Actually, the Noctua NF-F12 also uses the magnetic bearing system, although they call it their "SSO Bearing". The warranties offered are 5 years for the ML120, and 6 years for the NF-F12, not much different. I do know that Noctua fans have had for years a reputation for long life, but I suspect the ML120 would do similarly.

Performance specs for the two are different. The ML120 specs at max speed (2400 rpm) are 75CFM airflow and 37dBA noise with a maximum backpressure (for zero airflow) of 4.2mm H2O. The NF-F12 at 1500 rpm can deliver 93.4 m³/hr = 55 CFM and 22.4 dBA noise with a max backpressure of 2.6 mm H2O. If you sketch out a graph of airflow versus backpressure for those two you will find that throughout the range the ML120 unit will deliver more airflow against the same backpressure than the NF-F12 will, but at higher noise levels. Looked at another way, for the same airflow (as required by the fan control system for a particular CPU temperature) through the same backpressure (set by the radiator construction), the ML120 will be required to run at a smaller fraction of its max speed (although that may be pretty much the same speeds for the two fans) and will generate much less noise than its max speed noise. However, whether that is quieter than the NF-F12 at that point is not predictable. But what this does come down to is "reserve" cooling capacity. If you expect to run only at modest workloads, either fan will do the job well. But if you expect to be pushing the limits with sustained high workloads and high CPU temperatures, the ML120 fans have much more high-end airflow capacity to keep up with that need for high heat removal but they certainly would generate more noise under those high speed conditions.

The original SP120L fans included with the H100i system perform similarly to the NF-F12's but have higher top end performance (but less than the ML120's). However, those fans generate about the same noise as the ML120's, so for similar noise generation, the ML120's will produce much higher air flow; thus, the ML120's probably will be run slower and generate less noise if they are run to produce the same air flow as the SP120's. Again, this also means that the ML120's have more high-end reserve capacity than the SP120's if your workload is high.

 

[Tempas]

thank you!

 

[Paperdoc]

Thanks for Best Solution.

I thought after my last post I should call your attention to another fan option by Noctua. The ML120 PWM from Corsair is a high-performance 4-pin fan running at 2400 rpm max to deliver 75 CFM air flow at 37 dBA noise, with max backpressure of 4.2 mm H2O. The Noctua NF-12 iPPC-2000 PWM is also a 4-pin design running at 2000 rpm max to deliver 122 m³/hr = 72 CFM air flow at 30 dBA noise, max backpressure 3.9 mm H2O. So looking at similar high-performance models, the Noctua has slightly lower max performance but at less noise. By the way, IF you choose to get a Noctua fan, they often come with a little accessory to insert in its wiring called the "Low Noise Adapter". This device is for use when you do NOT have automatic fan control available because it is connected directly to your PSU. All it does it reduce the voltage supply to the fan so that it cannot reach its max speed and performance. When you are using some automatic fan speed control system, do NOT use that accessory - it interferes with control and prevents you from using its high performance ability when it is needed.