Review: be quiet! Pure Rock 2

Test Methodology and Performance

Notes

The arrival of our 2020 Test Platform allows us to start afresh with CPU cooler testing. The new PC features a 16-core, 32-thread AMD Ryzen 9 3950X processor and 32GB of dual-channel G.Skill Trident Z Neo DDR4 memory set to run at 3,200 using the built-in profile.

A Fractal Design Define 7 chassis is configured with its three stock Dynamic X2 140mm fans connected to the integrated hub and attached to a single motherboard header. Coolers are tested using default out-the-box settings, and to intensify the challenge while minimising noise, all fan headers are set to the 'Silent' profile within the Asus BIOS.

When testing liquid coolers, the pump is connected to the motherboard's dedicated AIO header, and the radiator is installed in the roof of the chassis with fans configured to push air up through the radiator and out of the enclosure. Fractal Design's vented top panel is used with liquid coolers, and the sound-dampened solid panel is in place when testing traditional air coolers.

Actual CPU temperature is recorded and we also graph the delta temperature (CPU temperature minus ambient temperature). Last but not least, to give you an idea of cooler acoustics, we use a PCE-318 noise meter to measure overall system noise in both idle and load states.

Performance

Our benchmarks begin with the 105W AMD Ryzen 3950X CPU running at stock speeds. We use the popular and open source Blender creation suite to render the taxing Victor scene and record the average CPU temperature from the last five minutes of 100 percent load.

The debate between air or liquid will continue to rage, but the early signs clearly suggest that our new test platform favours the former. Despite the budget price tag, the be quiet! Pure Rock 2 slots in fractionally ahead of a Corsair Hydro Series liquid cooler when tested using stock settings. Will newer liquid coolers fare better? We're intrigued to find out, and will have a couple of latest-gen solutions on the test platform in the very near future.

Good coolers keep noise levels down to a minimum. There's very little to separate all three setups; they are each practically silent when idle and barely audible under load.

Here's where things become interesting. Upping the ante in a simple manner, we raise the multiplier to 43x on all cores, while increasing voltage to 1.3V. We know the chip can do it, and the bump in juice is enough to push the coolers closer to their limit.

be quiet!'s Pure Rock 2 might be a low-cost solution, but we're pleasantly surprised to find that it could withstand the entirety of the Blender run. Don't get us wrong - 103ºC is far hotter than we'd be comfortable with in the long run, and we suspect the cooler may fail on a hot summer's day - but what do you expect for £34?

And it's not called a be quiet! for nothing. Even under heavy load, the fan becomes noticeable but isn't off-putting. Solid performance and low noise, just the way we like it.