Be Quiet Pure Loop 2 FX 360mm Review: Colorfully Cool

German component company be quiet! (henceforth Be Quiet) has long shied away from RGB lighting. But in conjunction with the company's 20th anniversary, it launched an FX line of new and modified cases, air coolers and AIOs that embrace colorful lights, mostly in the form of the company's Light Wings fans. 

We've got one of the new FX coolers on our test bench, specifically the Pure Loop 2 FX 360mm. It's the larger of three new FX AIOs, with a 280 and a 240mm model also available. Aside from the RGB-ringed fans, the company also includes some rainbow glow in a ring around the cold plate, so if you're looking to light up the inside of your case in your color(s) of choice as well as keeping your CPU cool, Be Quiet has you covered here.

Most liquid coolers today are based on Asetek designs, which have the pump included in the CPU block, but this cooler features an in-house design by Be Quiet, which places the pump along the cooling lines near the radiator. Does Be Quiet's big and bright cooling beast keep CPU temps and fan noise low enough to earn it a spot on our Best AIO Coolers list? We'll have to put it through out testing regime to find out. But first, here are the specs, from Be Quiet.

Specifications for the Be Quiet Pure Loop 2 FX

New Testing Configuration

I'll be testing the Pure Loop 2 FX with Intel's i9-12900K. Due to the increased thermal density of the Intel 7 manufacturing process, as well as changes to core and component layouts, Alder Lake CPUs are more difficult to cool than previous generation CPUs in the most heat-intensive of workloads. This means that coolers that kept previous generation products like the i9-10900K nice and cool sometimes struggle to keep Intel's i9-12900K under TJ max–the top temperature before the CPU starts to throttle. Many coolers I've tested aren't able to keep the i9-12900k under TJ max when power limits are removed in workloads like Cinebench and OCCT.

Please note that there are many factors that can influence your cooling performance. A system's motherboard can influence this, as there are motherboards on the market with CPU sockets that are not up to Intel's spec, which can cause warping or poor contact with the CPU. The case you use will also influence cooling results.

With this in mind, I'll be rating CPU Coolers in 3 different tiers.

Tier 1: These coolers are able to keep the i9-12900K below TJ max in most loads, with no power limits enforced. I expect only the best liquid coolers to meet this standard.

Tier 2: These coolers are able to keep the i9-12900K under TJ max with CPU power limits of 200W enforced. I expect most liquid and air coolers to meet this standard.

Tier 3: These coolers are able to keep the i9-12900K under TJMax with CPU power limits of 140W enforced.

Packing and Included Contents

Be Quiet's Pure Loop 2 FX is packaged in a large box that's approximately 2 feet in length, with molded cardboard for protection.

Included with the package are the following:

• 360mm Liquid Cooler
• 3x 120mm Light Wings Fans
• Mounts for all modern CPU sockets, including LGA1700 & upcoming AM5 motherboards
• Zip Ties
• Thermal Paste
• User Manual
• aRGB & Fan Controller Hub
• Extra Coolant

Cooler Installation

Installing the Be Quiet Pure Loop 2 FX was fairly simple. To begin, you secure the backplate screws to the backplate using the O-rings. Once the backplate is pressed against the motherboard, screw in the standoffs to secure it. Next, use the screws to secure the mounting brackets to the standoffs. Finally, attach the CPU block.

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What's different than other coolers?

The Pure Loop 2 FX is user-refillable and includes extra coolant.

Most AIOs are not user serviceable – which means if/when a certain amount of coolant escapes (via evaporation or leaks) they have to be thrown out. Be Quiet not only allows you to refill the coolant using an easy-to-access port covered by a screw, but also includes spare coolant in case you ever need it. That said, unless you plan on using your cooler for several years, across multiple platforms –which tends to be difficult given socket changes requiring new mounting hardware– coolant loss isn't usually a major issue with AIOs.

In-house Pump Design

The vast majority of Liquid Coolers on the market today are based around Asetek designs (licensed or not), with pumps integrated into the CPU block. But the Pure Loop 2 FX incorporates an in-house design from Be Quiet, where the pump is located near the radiator, along the cooling lines.

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There's more to a liquid cooler than just its radiator and pump. The fans have a huge impact on cooling performance and noise levels. Included with the Pure Loop 2 FX are Be Quiet's latest Light Wings fans, which include ARGB lighting in a ring around the blades – a first for a Be Quiet product, although the company launched several products with its Light Wings fans as part of a new FX lineup.

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New Testing Configuration

I'll be testing the Pure Loop 2 FX with Intel's i9-12900K. Due to the increased thermal density of the Intel 7 manufacturing process, as well as changes to core and component layouts, Alder Lake CPUs are more difficult to cool than previous generation CPUs in the most heat-intensive of workloads.

This means that coolers that kept previous generation products like the i9-10900K nice and cool sometimes struggle to keep Intel's i9-12900K under TJ max. Many coolers I've tested aren't able to keep the i9-12900K under TJ max when power limits are removed in workloads like Cinebench and OCCT.

Please note there are many factors other than the CPU cooler that can influence your cooling performance. A system's motherboard can especially influence this, as there are motherboards on the market with CPU sockets that aren't up to Intel's spec, which can cause warping or poor contact with the CPU. The case you use will also influence cooling results.

With Alder Lake's cooling demands in mind, I'll be rating CPU Coolers in 3 different tiers.

Tier 1: These coolers are able to keep the i9-12900K below TJ max in most loads, with no power limits enforced. I expect only the best liquid coolers to meet this standard.

Tier 2: These coolers are able to keep the i9-12900K under the TJ max threshold with CPU power limits of 200W enforced. I expect most liquid and air coolers to meet this standard.

Tier 3: These coolers are able to keep the i9-12900K under TJ max with CPU power limits of 140W enforced.

Testing Methodology

To test the limits of a cooler's thermal dissipation capabilities, I run two primary stress tests: Cinebench and OCCT each for 10 minutes. While this may be a short amount of time, it is sufficient to push most coolers - air and liquid - to their limits.

While stress testing in Cinebench, I run both with power limits removed and with an enforced 200W CPU power limit. In this test setup using MSI’s z690 A Pro DDR4 Motherboard and Be Quiet’s Silent Base 802 Computer Case, only the best coolers are able to pass Cinebench testing when power limits are removed.

I don’t test OCCT without power limits because attempting to do so results in CPU package power consumption jumping to over 270W and instantly throttling with even the best AIO coolers. Instead, I test at 200W to give coolers a chance at passing. I also include 140W results to give data closer to a lower-end CPU, such as AMD’s Ryzen 5600x or Intel’s i5-12400.

Core i9-12900K Thermal Results

Cinebench Test Results

Running Cinebench without power limits is the most thermally demanding load in my testing, and most coolers don't pass this specific test. The Pure Loop 2 FX managed to pass – but just barely. It did peak at the TJ max temp, but the CPU didn't throttle.

When power limits are restricted to a more reasonable 200W, both with the default fan curve and while limited to 50%, the Pure Loop 2 does well. Here it was 2 degrees Celsius behind Cougar's Poseidon GT360 at the default fan curve, and 2 degrees ahead when 50% speeds are enforced.

OCCT Test Results

I usually like to run OCCT's small set stress testing for stability when overclocking, but on Alder Lake I haven't found a cooler that's capable of handling OCCT without throttling unless power limits are enforced.

I test OCCT at 200W to demonstrate a thermally demanding load, but also with a 140W power limit enforced to show how these coolers might perform with a CPU that's easier to cool, like Intel's i5-12400 or AMD's Ryzen 5600X.

OCCT's thermal results were a bit different than the Cinebench results. Across all power limits and fan settings, the Pure Loop 2 FX performed slightly behind Cougar's Poseidon GT360, but it also ran quieter than Cougar's AIO in all of these tests.

Noise Levels and Acoustics

To test noise levels, I used the SLM25TK Sound Level Meter positioned 18 inches behind the rear of the Be Quiet Silent Base 802 PC case, and recorded early in the morning to achieve the lowest noise floor possible. The chart below shows averaged results, measured over the course of five minutes, to account for sudden variations in measurements.

In most situations, the Pure Loop 2 FX will run rather quietly. When limited to 50% fan speeds, it is the quietest cooler of the three units tested for this review. When run at maximum fan speeds, the Pure Loop 2 isn't exactly silent – but it does run quieter than both DeepCool's and Cougar's AIOs. The company is true to its name, it seems.

Conclusion

I wondered if the Pure Loop 2 FX would pass my testing because when I tested the first-generation Pure Loop AIO, my results weren't the greatest. But I was pleasantly surprised to find Be Quiet's Pure Loop 2 FX greatly improved and capable of cooling the i9-12900K even in demanding workloads. Lovers of silence will be pleased to know that this is the best-performing cooler I've tested thus far when fan speeds are limited to 50%.

During its initial launch, the Pure Loop 2 FX will be on sale at various retailers for up to $30 USD off the MSRP of $154.90 USD, through the end of September 2022 (or while supplies last). If you can find this cooler at that price, it's a steal if you like good, quiet cooling performance and lots of RGB.

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