Sound Level Testing
While we were testing cooling capabilities, as outlined in our recent introduction article, we were also tracking the sound level of each of the coolers using a Risepro SPL meter attached to a boom arm pointed directly at the fans of the radiator at a distance of 12 inches. We recorded the dB(A) level for each fan and pump speed tested. The ambient room sound level measured 33 decibels. Displayed below are the results of our Stock Clock Testing.
100% Fans – 100% Pump
At maximum fan levels, the Corsair H115i Platinum hit 49.4 dB(A). The ASUS Ryujin 240 was right behind it along with the SilverStone PF240-ARGB at 49.8 dB(A). The Enermax AQUAFUSION 240, our other 240mm cooler, hit 53.4 dB(A). From a subjective perspective, all of these coolers sounded loud but not high pitched. However, the ASUS ROG Ryujin 240 did seem to produce less pump noise than other units we have had to test. Another unique feature that impacts the noise levels here is the fan on the water-block. It was set to 30% (in all tests) because any higher than that and the fan on the water-block sounded like a hairdryer trying to achieve low earth orbit. For the rest of the coolers, we suspect the difference in sound is, mostly, related to the maximum RPM of each fan (SilverStone/Enermax and Corsair units at ~2200 RPM and ~1800 RPM respectively with the ASUS Ryujin 240 splitting the difference at ~2000 RPM).
1500 RPM Fans – 100% Pump
Dropping down to 1500 RPM, the SilverStone PF240-ARGB took the lead at 40.9 dB(A) and the ASUS ROG Ryujin 240 was just 1.7 dB(A) behind it at 42.6 dB(A). The PF240-ARGB is getting into the comfortable range at this point, but the ASUS ROG Ryujin 240 was still giving us a bit of a droning sound here. It was firmly in the middle of the pack though and that is with an extra, tiny, fan.
1000 RPM Fans – 100% Pump
When we lowered the fans down to 1000 RPM, the ASUS ROG Ryujin 240 went toe to toe with the Enermax AQUAFUSION 240 at a value of 37.4 dB(A). The SilverStone PF240-RGB was a touch louder at 38.7 dB(A).
600 RPM Fans – 100% Pump
Lowering the fans to 600 RPM (the lowest level we could keep them spinning at), the ASUS ROG Ryujin 240 joins the Enermax AQUAFUSION 240 to post a value of 35.8 dB(A). The SilverStone SilverStone PF240-ARGB came in at 37.4 dB(A). At this fan level, the whirr of the pump was louder than the fans and there was no real difference between the sound here and at 1000 RPM for the ASUS ROG Ryujin 240.
600 RPM Fans – 50% Pump
Finally, reducing the pump speed to 50% caused all of our review units to tie at 35.8 dB(A) except for the Enermax AQUAFUSION 240 which did marginally better. We could not ascertain a difference between ambient noise in the room (measuring 33 dB(A)) and the AIOs running.
Overall, the ASUS ROG Ryujin 240 mm was consistently one of, if not the, quietest coolers we have tested to date. In reality, it has been a dog fight among our 240mm coolers so far in this regard. Thus, it was not that surprising to see another 240mm unit do well here. However, coming from a brand that we don’t see quite as many cooling solutions from, ASUS, and including an extra, tiny, fan on the pump, this is an impressive result. With that said, let’s move on and recap all of this for you today!