Good cooler with too strong competition
19/12/2022
Translation: machine translated
The Pure Rock LP from Be Quiet is a new, flat top-down cooler for small systems. The part provides pleasant temperatures for the CPU - but the direct competitor does it even better.
If you choose the small form factor Mini-ITX for your PC, you have no room for a huge cooler. If there is enough space for an all-in-one water cooling system, it is usually the best choice. In some cases, however, not even that is possible. Here, only top-down coolers that embed themselves in the mainboard and are not significantly higher than it will help.
With the Pure Rock LP, Be Quiet has a new model of this kind on offer. In the test, it proved to be efficient. However, it is not enough to win against the Noctua NH-L9a.
Scope of delivery and assembly
The Pure Rock LP comes in a plain, small black box. The heat sink is already fitted with the corresponding 92-millimetre fan. The mounting material for all common AMD and Intel sockets is also included. The heat-conducting paste has already been applied.
Three six-millimetre-thick aluminium heat pipes conduct the heat away from the copper CPU contact plate. The waste heat is then released into the environment via 56 cooling fins. To distribute it better, the 92-millimetre fan blows down from above. It rotates at a maximum of 2500 revolutions per minute. The heat sink measures 92 × 92 × 30 millimetres without the fan. This adds 15 millimetres in height. It is connected to the mainboard via a 4-PIN PWM connector.
The cooler is screwed onto the mainboard from the rear for Intel and AMD sockets. Mounting is simple, but should be done outside the case for space reasons.
The cooler is mounted on the back of the motherboard.
Cooling efficiency put to the test
I tested the Pure Rock LP, as well as competing products, on the open testbench. I am aware that conditions are different in a small case. Mini-ITX cases differ more than ATX cases in terms of their cooling performance. Therefore, a test in one would not be more representative, as it would only be meaningful for that one enclosure.
I'm pitting Be Quiet's new cooler against Noctua's NH-L9a. As a reference, I use the slightly larger Big Shuriken 3 from Scythe, which I usually use for mini-ITX case tests. My test system is made up of the following additional components:
To push the CPU to its limit, I run AIDA64's system stability test. With the software HWInfo64 I record the temperatures of the CPU. In the following graph you can see how efficiently the cooler dissipates the heat.
As you would expect, the Big Shuriken 3 cools most efficiently due to its size. This applies to idle as well as under load. When the system is idle, the CPU temperature with the Pure Rock LP is 39 degrees Celsius. This means that the CPU is warmest in this state compared to the other two coolers. The new one from Be Quiet also performs worse than the competition under load. The difference to the NH-L9a is two degrees Celsius after 20 minutes. Expressed as a percentage: the Pure Rock LP gets 2.6% hotter at 78 degrees Celsius. Compared to the Noctua cooler, it has 14 per cent less cooling surface available. Viewed this way, the Pure Rock LP even cools more efficiently than the Big Shuriken 3 with 50 percent more cooling surface and a larger fan.
Source: Kevin Hofer
Source: Kevin Hofer
Nevertheless, Be Quiet's new model cannot compete with the NH-L9a in absolute terms. Nor can the Pure Rock LP list the larger cooling surface of the competition as an advantage. The Noctua cooler is 22 millimetres longer, but eight millimetres deeper. The length will not play a role with most mainboards, but the height will, depending on the PC case. So here, too, the advantages lie with Noctua.
Source: Kevin Hofer
Source: Kevin Hofer
The Pure Rock LP is also behind the competition in terms of noise development. When idling, it is barely audible at 35 dB measured from a distance of 30 centimetres, just like the Noctua fan. Even under full load, the fan is relatively quiet at 40 dB, but one dB louder than the competing products. Admittedly: You can hardly hear the difference in practice.
Seldom does a system reach such limits as in the test with AIDA64. That's why I run the integrated benchmark of "Shadow of the Tomb Raider" in 1080p resolution with the highest default settings. In this way, the test CPU with integrated graphics is also properly challenged. However, the game would not be playable this way.
Once again, I measure the temperature with HWInfo64. Here, too, the Pure Rock LP performs worst with a maximum of 65 degrees Celsius on the CPU. At a maximum of 61 with the Noctua NH-L9a and 59 degrees Celsius with the Big Shuriken, the CPU remains cooler. These are all temperatures that are within reason.
Conclusion: Good, but not good enough
The Pure Rock LP is a good fan for small systems. The problem: with the Noctua NH-L9a, there is one that does it even better. It runs quieter, cools better and is equally expensive - at least in Noctua brown. The black version, on the other hand, is much more expensive. That's why I can only recommend the Be Quiet if you absolutely want a black fan.
Kevin Hofer
Senior Editor
kevin.hofer@digitecgalaxus.chFrom big data to big brother, Cyborgs to Sci-Fi. All aspects of technology and society fascinate me.
