Noctua NH-D15: Update to an Icon

Cooling
Viewing page 5 of 6 pages. Previous 1 2 3 4 5 6 Next

STOCK FAN MEASUREMENTS

Specifications: Noctua NH-D15 Stock Fan
Manufacturer Noctua Power Rating 1.56 W
Model Number NF-A15 PWM Airflow Rating 140.2 m³/h
115.5 m³/h with L.N.A
Bearing Type SSO2 Speed Rating 1500 RPM
1200 RPM with L.N.A
Frame Size 150 x 140 x 25 mm (120 mm holes) Noise Rating 24.6 dBA
19.2 dBA with L.N.A
Hub Size 43 mm Header Type 4-pin PWM
Blade Diameter 133 mm Starting Voltage 4.5 ~ 5.0 V
Cable Length 20 cm Weight 160 g
Corner Type Open Retail Availability No
Additional notes:

The NH-D15 shares the same stock fan as the NH-U14S, both dubbed the "NF-A15 PWM." Noctua sells a fan with the same model number but it's a slower variant with a nominal rotational speed of 1200 RPM rather than 1500 RPM. Low noise adapters (L.N.A) are included, which bring the fan speed down to about 1200 RPM, but if you plan on using PWM, they can be better utilized elsewhere in your system.



The stock fan's range according to Fan Xpert2. PWM control on the top top, DC control on the bottom.

According to ASUS Fan Xpert2, the stock fan can effectively operate at less than 200 RPM under PWM control. The threshold for voltage control is in the 700~800 RPM range, though we found that both fan samples could reliably start with slightly less than 5V (<700 RPM).

Stock Fan Measurements
Voltage
Speed
One Fan
Two Fans
12V
1480 RPM
31 dBA
33 dBA
9V
1190 RPM
25 dBA
27 dBA
7V
960 RPM
18~19 dBA
20~21 dBA
6V
840 RPM
16 dBA
17 dBA
5V
720 RPM
13 dBA
13~14 dBA
Measuring mic positioned 1m at diagonal angle from the center of the heatsink.
Ambient noise level: 10~11 dBA.

Measuring 33 [email protected], the stock fans are quite loud at their top speed of ~1500 RPM. The low noise adapters effectively brings them down to 9V or ~1200 RPM, but they're not particularly quiet at this level either; 7V adapters would've been better suited. The fans require a drop to about 900 RPM to hit the 20 [email protected] level and are barely audible near the bottom of their operating range on voltage control.

As we've stated in a past fan roundup and the NH-U14S review, the NF-A15 has an somewhat inferior sound to our reference NF-P14, and this is exacerbated in the NH-D15's case as there are two of them. Each fan is buzzier than the reference model at higher speeds, and at 7V, develops some scratchiness. When paired up, they develop a steady mid-frequency hum that stands out at 7V and above. It's not particularly unpleasant but noticeable compared to two NF-P14's, which have a smoother acoustic profile with less tonality when producing equivalent noise levels. Otherwise, the sound produced is generally innocuous.

TEST RESULTS

Test Results: Noctua NH-D15
Fan Voltage
Single Fan
Dual Fan
Thermal Rise
12V
31 dBA
36°C
35°C
33 dBA
9V
25 dBA
37°C
36°C
27 dBA
7V
18~19 dBA
39°C
38°C
20~21 dBA
6V
16 dBA
41°C
39°C
17 dBA
5V
13 dBA
44°C
40°C
13~14 dBA
Reference 140 mm Fan (NF-P14)
12V
29~30 dBA
38°C
35°C
32 dBA
9V
22 dBA
40°C
36°C
24 dBA
8V
19 dBA
42°C
38°C
21 dBA
7V
15 dBA
43°C
39°C
17~18 dBA
6V
12 dBA
46°C
40°C
14 dBA
Measuring mic positioned 1m at diagonal angle from the center of the heatsink.
Ambient noise level: 10~11 dBA.

The NH-D15 was an excellent cooler, generating a thermal rise above ambient of just 40°C at 5V and 35°C at 12V, a very tight range considering the varying noise levels generated. Single fan performance wasn't much worse except when the fan voltage was lowered to 5V (720 RPM). Despite this, the noise reduction wasn't great enough to make it more efficient overall. Replacing the NF-A15's with our reference NF-P14's produced nearly identical results, except in the one fan configuration, which greatly favored the NF-A15, especially at higher speeds.



Previous 1 2 3 4 5 6 Next

Cooling - Article Index
Help support this site, buy from one of our affiliate retailers!
Search: