The Be Quiet! Dark Rock Pro 5 CPU Cooler Review: When Less Is More

Testing Results, Maximum Fan Speed

To begin with, we are having a look at the Be Quiet! Dark Rock Pro 5 with its stock fans running at their maximum speed.

The Be Quiet! Dark Rock Pro 5 exhibits a very good average thermal resistance of 0.1025 °C/W at its maximum fan speed of 1700 RPM. This efficiency is particularly notable under higher loads, aligning with its design geared towards handling demanding CPU applications. At first sight, it appears as if it falls significantly behind the Dark Rock Elite in terms of thermal performance but we need to remember that the Dark Rock Pro 5 has significantly slower fans installed.

The cooler's Silent Wings PWM fans are engineered to maintain low noise levels during peak operation. At full speed, the Dark Rock Pro 5 generates a noise level of approximately 36.6 dB(A). This level of noise, while not entirely silent, is remarkably low for a cooler operating with two fans, reflecting Be Quiet!'s commitment to balancing cooling performance with reduced acoustic output.

Testing Results, Low Fan Speed

In this test we are switching things up a bit, taking a look at the cooler’s performance with the Silent Wings fans taken down to half speed.

When the fan speed of the Be Quiet! Dark Rock Pro 5 is reduced to 850 RPM, there is an expected decrease in thermal performance. The average thermal resistance at this reduced speed is measured at 0.1301 °C/W. Although this thermal performance is more than adequate for daily usage, it has the Dark Rock Pro 5 falling behind many competitive solutions in terms of raw thermal performance. Once again, we need to take into account the low speed of the cooling fans.

Reducing the speed of the Silent Wings PWM fans to half results in a massive decrease in noise output, dropping to 32 dB(A). At this noise level, the cooler is practically inaudible, making it noticeable only in extremely quiet settings where no other noise sources are present and with the observer very close to the cooler. Under realistic operating conditions, it would be nearly impossible to discern the noise coming from the Dark Rock Pro 5, even in a dead-quiet environment.

Thermal Resistance VS Sound Pressure Level

During our thermal resistance vs. sound pressure level test, we maintain a steady 100W thermal load and assess the overall performance of the coolers by taking multiple temperature and sound pressure level readings within the operating range of the stock cooling fans. The result is a graph that depicts the absolute thermal resistance of the cooler in comparison to the noise generated. For both the sound pressure level and absolute thermal resistance readings, lower figures are better.

Out thermal resistance versus SPL chart is highly illuminating regarding the overall performance of the Dark Rock Pro 5, especially in relation to its mightier Dark Rock Elite version. The Dark Rock Pro 5 has almost exactly the same noise-to-performance ratio as the Dark Rock Elite, with the sole exception of having a slightly lower operating range. Simply put, the Dark Rock Pro 5 can operate more quietly but cannot reach as high a thermal performance as the Dark Rock Elite. For the most part of their operational range, the two coolers have nearly identical performance. This was not unexpected, taking into account that both coolers share the same body and only their fans change.