One noise row, sometimes with a ceiling attached
Each product's technical data carries a single "Noise level" row in dBA. On the Core fans a maximum follows in brackets, as in "43.0 (Max:45.0) dBA".
Standalone fan pages stop there, with nothing on speed, voltage or distance. Only the Core Ocean T38 AIO pages say more. Their fan row is headed "Noise level (rated voltage, mute room, distance 1 m)".
The Rise Aurora fans break the pattern. Their label is "Volume max", followed by "max. 31.5 dB(A)" or "max. 38.4 dB(A)", and since those are ceilings this page leaves both out of every ranking. Why missing test conditions make cross-brand comparison shaky is the subject of our explainer on comparing decibel ratings.
Which Alphacool 120mm fan is quietest?
The Apex Stealth Metal Fan 2000rpm, at 24.6 dBA. The Core 120mm 4000rpm sits at the other end with 49.5.
| Model (article no.) | Noise row | Top speed | Airflow | Static pressure |
|---|
| Apex Stealth Metal 2000rpm (13819) | 24.6 dBA | 2,000 rpm | 47 CFM | 2.09 mmH2O |
| Core 120mm 2500rpm (24852) | 36.6 dBA, max 37.8 | 2,500 rpm | 72.63 CFM | 2.42 mmH2O |
| Apex Stealth Metal Power 3000rpm (13823) | 40.1 dBA | 3,000 rpm | 70.98 CFM | 4.23 mmH2O |
| Core 120mm 3000rpm (24844) | 43.0 dBA, max 45.0 | 3,000 rpm | 93.6 CFM | 7.83 mmH2O |
| Core 120mm 4000rpm (24845) | 49.5 dBA, max 51.5 | 4,000 rpm | 119.8 CFM | 12.67 mmH2O |
Amazon had no single listing for the 2500rpm Core, so it stays in the table and out of the picks. Noctua, Arctic and other 120mm fans are compared in our 120mm fan guide.
Alphacool's 140mm fans run from 38.3 to 51.0 dBA
Three Core models make up the 140mm range, and noise climbs with speed.
| Model (article no.) | Noise row | Airflow | Bearing |
|---|
| Core 140mm 2000rpm (24853) | 38.3 dBA, max 40.0 | 103.03 CFM | Hydraulic |
| Core 140mm 2500rpm (24846) | 43.3 dBA, max 45.0 | 115.56 CFM | Two ball bearings |
| Core 140mm 3200rpm (24847) | 51.0 dBA, max 53.0 | 153.9 CFM | Two ball bearings |
A lead time instead of stock on Amazon kept the 3200rpm fan off the picks. More 140mm choices from other makers sit in our 140mm case fan guide.
Decoupling, by Alphacool's account. A damping system keeps the blades, motor and suspension "completely decoupled from the metal frame", and a closed ring wraps the impeller tips.
Speed plays a part as well. The Apex tops out at 2,000 rpm, below every Core 120mm, and it moves 47 CFM where the 3000rpm Core moves 93.6. Yet the Core 140mm 2000rpm reaches that same top speed and still lists 38.3 dBA, 13.7 more than the Apex. Alphacool never claims the two were measured alike, so part of that gap could belong to the test bench and not to the fan.
The Core Ocean T38 is the AIO with both rows
Per fan, the T38 lists 34.3 dBA, maximum 36, at 1 m in a mute room, and its pump lists 35 dB. No other Alphacool AIO prints both.
Size changes nothing in those rows. The 280mm and 420mm versions share one 140mm fan and one 2,500 to 3,500 rpm pump, so a bigger radiator simply means another fan.
The expandable Eisbaer line reads differently. On the Eisbaer Aurora HPE Edition 360 and the Eisbaer Pro HPE Aurora 360, the Rise Aurora fans carry "max. 31.5 dB(A)" and the DC-LT2 pump gets no noise row, while the Eisbaer Pro Aurora 360 and Eisbaer Aurora LT360 pages print nothing at all. Liquid coolers from other brands are lined up in our AIO cooler guide.
Two T38 sizes are still on Alphacool's site
On November 10, 2026, the CPU AIO category held two Core Ocean T38 coolers, the 280mm (13053) and the 420mm (13054).
Links to the 240mm (13051) and 360mm (13052) ended on a page not found. Resellers still listed both sizes on Amazon, but without a maker page nobody can confirm they are still made, and neither became a pick. The 280mm was in stock on Amazon that day and the 420mm in limited stock. Either gives the same fan and pump figures.
Do Alphacool pumps have noise ratings?
One does. The VPP655 PWM D5 pump's page and English datasheet both read "Noise level 35 dB(A), maximum 40 dB(A)".
Speed, flow and head are all printed for the DC-LT 2 2600rpm, the Laing DDC310 Single Edition and the VPP Apex. Noise is not. The DDC310 page even bills itself as a "Low Noise Edition of the Laing DDC for absolute silence!" with no number behind the boast.
Watch the units. The Core Ocean pump's "35 dB" has no weighting letter and no distance, which makes it a different kind of figure from the VPP655's 35 dB(A) despite the matching number. Pump hum and the other sounds a PC makes are covered in our computer fan noise explainer.
The Rise Aurora fans are on their way out
Both Rise Aurora shop addresses end in "pht-eol", and a cross-sell box labels the 120mm "PHT EOL", though the pages still showed stock on November 10.
Their rows are ceilings, "max. 31.5 dB(A)" on the 120mm and "max. 38.4 dB(A)" on the 140mm, so neither is ranked. At 800 rpm, the product text adds, each fan is "almost silent".
No number comes with that.
