Which radiator fans to use?
Which radiator fans to use?
I have a loop setup with two GTX1080 cards (factory overclocked) and one 6900K processor (moderately overclocked to 3.8-4.0Ghz). I'm cooling it using a 1 GPM flow with 11x120mm radiators (HardwareLabs Nemesis GTX 2x4 + 1x3) and fans arranged in a push-pull configuration, which results in a loop TDP of around 750W.
I plan to run 22 Noctua P12 fans in ULN mode (1.21 pressure, 37CFM, 900RPM, 12.6DDB ea) to manage the heat. These fans will likely have DCIMFlex radiator covers attached, causing about a 20% efficiency drop.
Will this configuration be sufficient?
If necessary, I could upgrade to NF-F12s (1.83 pressure, 1200 RPM, 44 CFM, 19dB), but this would significantly increase noise levels and go against my goal of maintaining a quiet build.
No, I prefer not to use PWM fans or GentleTyphoon-15 1850 RPM fans.
Thanks for your assistance!
I don’t have prior knowledge of custom loop rads, but I can share what I’ve experienced with Corsair closed-loop rads when using push/pull setups with a few different static pressure fans. I began with a 120x38mm rad (probably H80?) and used the Cougar CFD120 LED fans (64cfm and 1.74mmh2o pressure). They performed well, were quiet at full RPM, though I didn’t notice much airflow through the rads. Later, when upgrading to a new motherboard, I switched to the H105 model, thinking it would be better. The SP120L fans (73 cfm, 3.9mmh2o @2700rpm) reduced my temperatures by about 8 degrees at the same overclock level under full Prime95 load (reaching a max of 57°C). Even though they made a noticeable hum at full speed, they cooled significantly better and provided much more airflow compared to the Cougar units. Now I have the H105 with the stock SP120L fans on top and the Corsair SP120 Performance Edition fans on the bottom. The SP120 fans (62.74cfm, 3.1mmh2o @2350rpm) move slightly less air through the rad than the SP120L, but I barely hear them. I keep the SP120s running at full speed and the SP120Ls only rev up when temperatures rise higher, which is exactly what I prefer. Overall, if I were starting fresh, I’d recommend going back to the SP120 Performance editions. They’re available in a twin pack at a reasonable price and deliver strong airflow with minimal noise. I haven’t tried Noctua fans before, but they seem promising too; however, their higher cost keeps me from considering them. Based on the specs you mentioned, the Noctua P12 fans appear to have low pressure, so for rads like these, a higher static pressure fan would be more suitable. Especially if the filters are clogged. I definitely felt a noticeable improvement in airflow after installing the rads, and from a spec standpoint, the Corsairs look similar to the P12s without the LN adapter. I’d definitely give the SP120s another go if you’re interested. They also came with an LN adapter, though I usually use a fan controller instead. I’m currently overclocking an FX-8150 and found that stock speeds didn’t make much difference with the Cougars, but now the heat output is much more noticeable. Hope this helps!
In short, if I had to begin fresh with fans, the SP120 performance models would be the best choice again. I discovered them in a twin pack at a reasonable cost compared to other options, and they deliver significant airflow without excessive noise in my tests. For me, these units are probably too powerful and noisy (up to 36 dB) without a fan controller. If I had more space for the radiator and were pushing GPU overclocks, they could be worth looking into, but not for quiet builds. I’m not looking for top-tier cooling; just enough to keep things manageable. The challenge is figuring out the safe noise level.
If you’re after mid-range (1600-2000 RPM) radiator fans, consider the GentleTyphoon-15s (2.2 pressure, 1850 RPM, 28 dB in theory but strong in real use), or the Noctua NF12 models. These offer comparable pressure and CFM to the SP120s (2.61, 55 CFM) but at about half the volume (22.5 dB). The drawback is their higher cost and less attractive design.
Of course, the Noctua NF12s are similar in performance but noticeably quieter. The Corsair slim cooler you’re using (38mm) has a much higher FPI and likely demands more pressure than the GTX models (60mm, low-mid FPI, built for low RPM fans). That’s another consideration.
In real builds, I own a few Cougar vortex fans and use them occasionally. They work well as case fans, offering solid CFM, though they’re not optimized for pressure and are significantly louder without the included LNA. With the LNA, they become much more balanced. From a budget standpoint, they’re similar in price ($15 vs $20), but they’re excellent deals when bought in bundles.