Need to keep a hot CPU cool? Air coolers will do a decent job, but nothing excels at keeping temperatures down like a good AIO CPU cooler. There are many different AIO sizes, but none combines price, compatibility, and performance like the trusty 240 mm AIO. So if you need some extra cooling performance, it’s time to consider one of the best 240 mm AIOs for your rig.
240 mm AIO CPU coolers are a good step up from air cooling without the cost of larger, less-compatible 280 and 360 mm AIO CPU coolers. They don’t quite match the cooling performance of their bigger brothers, but they’re still solid options for those who need more performance than budget air coolers can provide. Let’s get started.
- Best 240 mm Liquid Cooler Overall: Arctic Liquid Freezer II 240 A-RGB has great thermals and low noise at a reasonable price.
- Best 240 mm Liquid Cooler Runner-Up: Cougar Aqua 240 offers excellent thermal performance at a great price but uses noisy, high-speed fans.
- Best 240 mm Liquid Cooler for RGB: Corsair iCUE H100i Elite Capellix performs decently and features great RGB lighting with its pump block LEDs and eye-catching ML120 fans.
- Best 240 mm Liquid Cooler With LCD Display: NZXT Kraken Z53 RGB has a clean white finish and an LCD pump block for all sorts of aesthetic fun.
- Best Budget 240 mm Liquid Cooler: ID-Cooling Auraflow X 240 has unexceptional performance for a 240 mm AIO, but its price (including RGB!) is hard to beat.
Our Favorite 240 mm AIOs
Arctic’s received a lot of praise for its range of Liquid Freezer II AIO coolers due to excellent price-performance ratios and low noise levels. So it’s probably no surprise that the Liquid Freezer II AIO 240 A-RGB also takes the cake here. It’s not quite as outstanding as its larger counterparts, but it’s still a top performer you would do well to check out.
Guru3D put the Liquid Freezer II 240 A-RGB through its paces with an Intel i7-4790K in stock and overclocked configurations. Unsurprisingly, the Liquid Freezer II 240 AIO cooler performed great with a stock 4790K, with Guru3D recording an absolute temperature of 59 degrees Celsius at 34 dBA of noise.
This puts it within spitting distance of larger AIOs like Arctic’s own Liquid Freezer II 360 A-RGB, which is impressive considering the price. It also competes with similarly-priced tower coolers like the Noctua NH-D15.
It struggled slightly with a 4.6 GHz overclock at 1.30 volts, with the i7-4970K hitting a maximum of 73 degrees Celsius over two runs of wPrime. It’s still a solid performer, though its 120 mm fans are significantly noisier at 41 dBA. You’ll be fine cooling an Intel i5-12600K, but you may want to upsize if you’re going to overclock something like an i9-12900K.
The Arctic Liquid Freezer II 240 A-RGB also excels in user-friendliness. It comes with pre-installed fans, and all the cabling is tidied up and routed from the factory. It’s just a matter of attaching the radiator and connecting the fan and RGB headers to your motherboard. It’s a minor touch, but one that not every other manufacturer does. So kudos to Arctic for that.
It’s also worth praising Arctic for its handling of a defective gasket issue that has caused some Liquid Freezer II units to fail. The company is offering a self-service repair kit to affected users to allow them to fix the issue without voiding the warranty. Note that the problem only affects units sold between May 2021 and March 2022; thus, you’re unlikely to be affected if you buy one now.
Overall, we think the Arctic Liquid Freezer II 240 A-RGB is one of the best AIO coolers for mainstream and higher-end rigs. It’s a great deal at around $110, especially considering its six-year warranty and included LGA 1700 mounting kit.
Some users might take issue with the minimal amount of RGB lighting on the pump head, but we don’t think that’s a huge deal considering its excellent cooling performance.
Don’t need ARGB? Consider the non-RGB Arctic Liquid Freezer II 240 for slightly under $100.
Cougar might not be a household name in cooling, but the company’s Aqua 240 AIO cooler is a strong contender that trades blows with some of the best on the market. It has one noticeable flaw, but its solid performance and keen price might make up for it.
The Aqua 240 is a capable performer, staying slightly ahead of the Arctic Liquid Freezer II 240 in KitGuru’s testing with an Intel i9-9900KS at various clock speeds. The two are closely matched at the 9900KS’ stock 4.0 GHz and a light 4.7 GHz overclock, with the Aqua 240 turning in a respectable 54.3 Celsius result. The Arctic, by comparison, trails slightly behind at 55.3 degrees.
The gap widens when pushing the 9900KS up to a more serious 5.1 GHz overclock. Here, the Aqua 240 keeps the CPU at 65.4 degrees Celsius while the Arctic trails behind at 68.3 degrees Celsius. The Arctic still turns in a good result for such a heavy overclock, but the Cougar Aqua 240 seems to have the edge when pushing CPUs to their limit.
Of course, this performance doesn’t come for free. The Cougar is noisy, especially at the fan speeds needed to compete with the Arctic Liquid Freezer II 240. The Aqua 240 registers 46.6 dBA of fan noise in KitGuru’s testing. Up against that much noise, the Arctic’s 40.2 dBA is positively silent in comparison.
On pure thermal performance alone, the Cougar Aqua 240’s impressive performance makes it likely one of your best options at a sub-$90 price point. However, its high noise output won’t be for everyone. But if you can live with that, then the Cougar Aqua 240 is a great AIO water cooler well worth considering.
“Corsair” and “RGB lighting” are an inescapable combo, and the Corsair iCUE H100i Elite Capellix AIO cooler is compelling proof of that. It combines Corsair’s much-loved ML RGB fans with an eye-catching pump head, offering great aesthetics backed up with decent thermal performance.
The iCUE H100i Elite Capellix is a competent performer, despite its clear focus on RGB lighting. Guru3D’s testing sees it neck and neck with our top pick, the Arctic Liquid Freezer II 240, in stock and overclocked tests with an Intel i7-4970K. The Corsair unit measured 60 and 71 degrees Celsius stock and overclocked respectively, solid numbers overall.
The H100i Elite Capellix manages these numbers without needing to get too noisy, either. Guru3D recorded 35 dBA of noise under load, rising to 41 dBA with the heavy CPU overclock. It will certainly be audible (like most 240 mm AIO coolers), but it won’t be too bad.
The H100i Elite Capellix’s lighting is arguably the star of the show. With 31 individually-addressable RGB LEDs in the pump head and 8 in each ML120 fan, the H100i Elite Capellix is a perfect canvas for whatever color schemes your creativity can come up with. The included iCUE Commander CORE RGB controller makes setting everything up a breeze, too.
Corsair ships the H100i Elite Capellix comes with two CPU block caps. The one you see in most product photos is the glossy black cap, which hides most of the RGB LEDs for a more laid-back look. The second cap is transparent and lets the full force of all 31 ARGB LEDs shine through.
Overall, the Corsair iCUE H100i Elite Capellix is one of the best 240 mm AIO coolers on the market if RGB is your priority. It’s not the only AIO with an RGB pump header, but the H100i Elite Capellix benefits from the extensive lighting customization afforded by Corsair’s iCUE software.
The Corsair iCUE H100i Elite Capellix is available in black or white. Corsair also sells the H100i RGB Pro XT, which comes with non-RGB fans for a lower price. Note that you’ll need to buy the LGA1700 retrofit kit if you want to use this with a modern LGA1700 CPU.
NZXT’s Kraken Z53 RGB is no longer the only 240 mm AIO cooler with an LCD on its pump block. However, its competitive cooling performance and eye-catching white finish mean it’s still our top choice for those looking for a flashy, showcase-ready AIO.
Hexus tested the Kraken Z53 with an AMD Ryzen 9 5950X and recorded a stock delta temperature under load of 38.6 degrees Celsius. That’s quite impressive for a 240 mm AIO cooling such a high-powered CPU. It also handled a 4.5 GHz all-core overclock reasonably well, keeping the 5950X at a 60.4-degree delta.
A 280 or 360 mm AIO cooler is a safer bet if you want to run a 5950X at those speeds, but the Kraken Z53 will do if it’s your only option.
Unfortunately, the Z53 RGB’s performance comes at the cost of high noise levels, with Hexus recording 37 dBA at stock and 41.4 dBA when overclocked. The overclocked result isn’t bad, but 37 dBA at standard clocks is a bit high. It likely has to do with the default fan curves, which push the fans to 100% too quickly. Thankfully, that’s something you can rectify quickly in NZXT’s CAM software.
CAM is also where you’ll find all the control for that fancy pump LCD. You can choose to show clock frequencies, CPU temperature, and GPU temperature, either individually or in a dual infographic mode. You can also set a custom .gif, which is likely 90% of the reason anyone even wants an LCD-clad pump block.
Overall, the NZXT Kraken Z53 is still the king of the hill if you want a 240 mm AIO CPU cooler with a lot of bling. It’s one of the priciest 240 mm AIO coolers available at around $250, so you’re paying a significant premium for the white paint and LCD pump block. But if those features are what you need to top off a showcase build, the extra money might be worth it.
If you’re buying this to use with a 12th or 13th Gen Intel CPU, note that you may have to request an LGA1700 kit from NZXT if you happen to get an older unit. All Kraken Z53s produced after 11/25/21 will include the bracket, but you may still find older stock floating around. Check out NZXT’s bracket request guide here for more help.
Liquid coolers are great, but they don’t come cheap. Most 240 mm AIOs start at around $100, which is significantly more than most air coolers. But one AIO bucks the trend by offering liquid cooling at an air-cooled price: enter the ID-Cooling Auraflow X 240.
The ID-Cooling Auraflow X 240 is a value-oriented 240 mm AIO CPU cooler that comes in at around $70. That’s cheaper than some high-end tower coolers, which is an excellent price point for a 240 mm AIO. As you might expect, however, this low price doesn’t come without compromise.
TechPowerUp ran wPrime on an Intel Core i7-8700K at stock and 4.8 GHz and recorded 62 and 79 degrees Celsius, respectively. The Auraflow X’s cooling performance isn’t bad, but the temps are on the high side for a 240 mm AIO. The overclocked result, in particular, is much higher than we’d like to see.
For context, Noctua’s similarly-priced NH-U12S tower cooler kept the i7-8700K at 58 and 78 degrees Celsius in stock and overclocked form in the same test. And it’s not that the Auraflow X 240’s sacrificing thermal performance for low noise levels, either: it hits a maximum of 49 dBA at full speed. That’s six dBA higher than the NH-U12S for little thermal benefit.
Yes, the ID-Cooling Auraflow X 240 performs decently and costs significantly less than many competing 240 mm AIOs. However, its sonic and thermal performance isn’t a significant improvement on a similarly-priced air cooler. Where does the Auraflow X 240 fit in?
If you’re just after a good CPU cooler for around $70 to $80, then you’re likely better off with the Noctua NH-U12S air cooler we mentioned above. It’s a lower-risk, lower-maintenance product that’ll run reliably with zero chance of catastrophic leaks or other potential AIO failures.
However, what if you need an AIO on a tight budget for space, component clearance, or aesthetic reasons? Then the ID-Cooling Auraflow X 240 becomes a viable, if not necessarily brilliant, option. Be aware of the compromises, and you’ll find a decent, if unspectacular, budget-friendly 240 mm AIO. It’ll likely outperform even the best 120 mm AIOs at a similar price.
240 mm AIOs vs. The Competition
Before you rush out and buy a 240 mm AIO, remember that they’re not your only option for CPU cooling. So let’s quickly compare 240 mm AIOs with two of their closest competitors, high-end air coolers and 280 mm AIOs, and see how they stack up.
240 mm AIOs vs. Air Coolers
Most good 240 mm AIOs trade blows performance-wise with the largest, highest-end air coolers, such as Noctua’s NH-D15. However, 240 mm AIOs can often run quieter than their air-cooled rivals due to their higher cooling efficiency and potential.
Let’s go back to Guru3D’s test results for the Arctic Liquid Freezer II 240. At 59 degrees under a stock load, it performs identically to the
It’s a bit less clear-cut noise-wise: the Assassin III beats the Arctic’s 34 dBA measurement by coming in at 32 dBA, while the Noctua
But numbers are only half of the picture. The other half is compatibility and installation, where 240 mm AIOs have an advantage.
The highest-end tower coolers are bulky and take up a lot of space in your case. They also obstruct parts of your motherboard, such as the RAM slots and fan headers. This can make installation and maintenance a bit of a chore. Cavi’s build here is a perfect example. Note how the
In contrast, a 240 mm AIO (or any AIO, for that matter) takes up much less space and leaves room for tall RAM and top-mounted fans. You can also build in narrower cases that may not have enough room for a tall air cooler.
Reliability is also worth considering when choosing between air and liquid. Air coolers are essentially failure-proof, while liquid coolers can leak and dry out over time. If you’re interested in finding out more about compatibility and reliability issues, check out our guide to liquid cooling vs. air cooling for a more in-depth look.
Overall, there isn’t an outright winner when choosing between a 240 mm AIO cooler and a high-end air cooler. Both have strengths and weaknesses, and it boils down to your priorities (and how much room you have in your case). You’ll have to step up to a 280 mm AIO or larger to find AIOs that definitively beat air coolers performance-wise.
240 mm AIOs vs. Larger AIOs
280 mm and larger AIOs have two clear advantages over 240 mm AIO coolers. Firstly, larger radiators have more surface area, which gives them extra cooling capability. This is particularly useful with high heat loads, such as a heavily overclocked CPU.
To illustrate this, let’s go back to KitGuru’s testing of the Cougar Aqua 240. At their Intel i9-9900KS’ stock 4.0 GHz clocks, larger AIO coolers like the Corsair H115i Elite Capellix only have a two-to-five-degree Celsius advantage over the Cougar Aqua 240:
However, cranking that i9-9900KS to 5.1 GHz puts a much more noticeable 10-degree delta between the 360 mm NZXT Kraken X73 and the 240 mm Cougar Aqua 240:
The second advantage is noise: the extra surface area allows for slower fan speeds without sacrificing themal performance. Let’s stick with KitGuru’s review to illustrate this. The numbers below show noise-normalized temperature results, with all AIO coolers set to run at 40 dBA. You can see that the larger AIOs perform noticeably better than the smaller ones here. They’re more efficient and don’t rely on high fan speeds quite as much.
If you’re trying to cool a monster CPU, get the largest AIO cooler that will fit in your case. But you won’t need that much cooling if you’re not trying to run an Intel i9-12900K at 5.1 GHz daily. That said, a larger AIO cooler might still be useful if you want to turn the fans down to get as much cooling with as little noise as possible.
It boils down to your budget and how much room you have in your case when settling on an AIO size. 240, 280, and 360 mm AIO coolers have their uses, and you can’t go wrong with any of the three, just as long as you know what you’re committing to.
Choosing a 240 mm AIO cooler can be tricky, as there’s often not much difference between many of them performance-wise. The fact that most companies use the same OEM means that thermal differences are often within margin of error. So it will boil down to factors such as noise, aesthetics, and price to determine the best 240 mm AIO cooler for your needs.
The Arctic Liquid Freezer II 240 A-RGB is a safe bet for most users, with its reasonable price point and good balance between thermals and noise. But those who want some bling for a showcase system will likely want to go for either the Corsair iCUE H100i Elite Capellix or NZXT Kraken Z53 RGB, depending on aesthetic preference.
All the best!