box - Arctic Liquid Freezer II 420 Review

As is going to be the obvious trend of this review, the Arctic Liquid Freezer II 420 can be considered ‘nothing more’ than a bigger variant of the 280 (and/or 360) versions. In some ways this is a Good Thing ™ but in others it is certainly anything but that. The shipping container itself easily falls into the former and not later category. Just as with the smaller siblings this Big Ass Box of Badassness is classic Arctic. The color pallet is attractive yet highly conservative. It is covered in pictures, information, detailed descriptions and generally speaking both shows and tells why you should be thinking about buying this particular CPU cooling solution over all the rest.

box o - Arctic Liquid Freezer II 420 Review

Internally it uses a combination of copious amount of cardboard with intelligent packaging to ensure your Liquid Freezer II model arrives safe and sound. Basically, it (once again) offers nearly everything we like to see in a shipping container with nothing that we dislike. The only way it could be improved is if it had a nice big sticker that said “reduced price” or “sale” on it…. considering how hard it is to find an Arctic Liquid Freezer II in stock (let alone the 420 variant) that may indeed be a tall order for even Arctic to accommodate.

access - Arctic Liquid Freezer II 420 Review

Moving on. As some people are already aware Arctic does not consider their Freezer II design to be static or ‘perfect’. Instead, it is a living breathing project that they are constantly tinkering with. This too is a Good Thing. When it came to their attention that the original internal electronic configuration was not playing nice with every motherboard’s “CPU” fan headers (i.e. it was incorrectly providing VRM fan rpm states and not pump rpm) they fixed it (‘rev.2’). When they figured out how to make the mounting hardware work better (and offer a couple degrees better cooling on Ryzen 3K and 5K CPUs)… they fixed their hardware and offered it to existing customers free of charge (‘rev.3’). When they received complaints over the new ‘stock’ AMD mounting hardware not being the easiest to use with some motherboards / and or causing clearance issues… you guessed it, they fixed their fix (‘rev.4’).

While some will argue that having to constantly tinker with a design is the mark of bad engineering, we feel the opposite. This willingness to admit to imperfection shows that they not only own up to their mistakes, and try to make it right, they continuously are trying to make their own designs better. That is a breath of fresh air and put Artic right up there with the likes of Noctua when it comes to customer satisfaction (and “toilet trained with a shotgun” levels of OCD). The downside is FOMO is in full effect with this line – as ‘tomorrow’ they probably will release a ‘rev.5’ and then a ‘rev.6’ and then etc. etc. etc. Honestly, even with the couple Liquid Freezer II rev.1’s we use, we have little inclination in upgrading them. We suggest you too not worry about the revision… as long as what you have works. If something doesn’t, call them up and they will make it right but don’t worry about it too much as they are mainly refinements/tweaks. Not complete overhauls.
Either way the included mounting hardware is top notch. Everything from a metal Intel backplate, to that new and highly advanced AMD top brackets, screams quality and innovation. The only issues are that the new rev.4 AMD equipment has dropped AM3 support from the combability list; they still do not include enough screws to mount six fans ‘out of the box’; and Artic still does not include a physical manual. Instead, you have to download it manually (either via their website or the QR code included in the box). Make no mistake. This is an excellent list of accessories. There just is still some room for improvement in the form of a Rev.5 release.

front - Arctic Liquid Freezer II 420 Review

On the truly positive side, with almost no caveats needed, Artic pre-mounts the three Arctic “P14” 140mm fans to the massive radiator for you at the factory. Yes, this only saves a few moments work but it is a time saving bonus feature. It also shows you the air direction that Arctic recommends – blowing the heat outside the case. In many ways we really, really like these 140mm fans as they have been optimized for high static pressure (2.4mm), low noise (0.4 Sone), and (thanks to Fluid Dynamic Bearings) longevity. How is Artic is able to do all that in a “25mm” form-factor without raising RPMs? Simple. They cheat. These are 27mm high/tall fans not 25mm. That does not sound like much but a couple extra millimeters on the fan blades’ height allows for more static pressure and a bit more CFM of air movement.

dim1 - Arctic Liquid Freezer II 420 Review

Honestly we are firm believe in “if you ain’t cheati’ you ain’t trying” and 2mm over spec’s is probably not going to cause installation issues. Put another way they are worth the 10 dollars each they retail for… even if they are going to be 8percent taller than you thought. The only issue we have with them is not the lack of LEDs or color; rather it is that while they do move more air than the 240/360’s P12 120mm fans (72.8CFM vs 53.6CFM), they are slower (1700rpm vs 1800rpm). People buy massive AIOs for performance (and less hassle factor than custom water loops). So here is a model that we disagree with Arctic’s classic ‘balanced noise’ approach… as it is relatively simple procedure to rpm limit a 2K fan to 1700RPM, but you cannot easily/safely overvolt a 1700rpm fan to 2000RPM. Furthermore, we know Arctic can make good 2K rpm range 140mm fans. Their very own BioniX P140 cruises along at up to 1950rpm with (slightly) higher CFM (77.6CFM) and higher static pressure(2.85mm). We have zero idea why any company would hobble their top-of-the-line AIO like this… but Arctic must have their reasons. To be fair, this is more nit picking than anything. We really do not care enough to swap them out for Noctua 2K or 3K IPC fans, but it still is a bit of a disappointment.

dim2 - Arctic Liquid Freezer II 420 Review

Moving on. Artic really do not like doing things by half measures and the 420 is no exception. Typically, with 420mm ‘long’ radiators companies like to start thinking about those pesky things like case combability. When they do that… they typically opt for a thinner rad so as to help make up for the longer radiator dimensions. Artic has not done that. Instead, they once again have opted for a thick 38mm radiator. Just like they do with smaller variants of the Freezer II series. We have to give them props for not comprising on the thickness, as if you have the fan horsepower to push air through them that extra 35 (vs 28mm) to 37 percent (vs 27mm) of rad depth, the extra surface area pays dividends. It pays dividends not only on the shear amount of heat it can handle (for example this is one of maybe three 420mm AIOs we would trust to be able to handle an overclocked Intel i9-10980XE) but how long it takes before it reaches it ‘temperature equilibrium’.

comp2 - Arctic Liquid Freezer II 420 Review

That last bit is a bit complicated to explain in detail but in simplistic terms… the more water a system has the longer it takes to heat up that water (think boiling time for a 1L kettle vs a 2L kettle). The longer it takes to do this, the longer the CPU runs at artificially low temperatures. Put another way, the more water it has in the loop the longer it takes before temperature becomes the limiting factor on short term ‘boosts’ in frequencies. With AIOs there is no secondary water reservoir so the amount of water for heat absorption is simply what will fit inside the block+tubing+radiator. Nothing more. Nothing less. So while a radiator with 35’ish percent more space does not mean 35 percent more overall water volume in the loop, it is a lot more water to absorb the heat… and artificially boost its perceived real-world performance abilities.

To further help boost the total amount of water in this closed loop cooling solution Artic (once again) uses 6mm Inner Diameter (12.4mm OD) tubing instead of the more typical 5.1mm ID tubing. That really is not that big of a difference but it does help. Unfortunately, other companies have gone even bigger with 7mm (or greater) ID tubing. We typically do not care much about the inner diameter of the tubing on an AIO as it is almost a rounding error in the difference (for example with 6mm ID that equates to a volume of 25.446ML vs. 18.385ML for 5.1ID vs. 34.635ML for 7mm ID vs. 45.235ML for 8ID when dealing with a total length of 900mm worth of tubing).

With that said, if you are purposely trying to build the best AIO why stop at “quarter inch” 6mm tubing and not go for “three eighths” / 9.525mm tubing… which many water-cooling enthusiasts typically use in their custom loops? Sure, it would only result in an extra ~38.68ML in the loop, and make the tubing that much more “difficult” to work with… but 420mm AIOs are all about no compromises.

cable - Arctic Liquid Freezer II 420 Review

Once again, this is not a major complaint or issue really worth worrying about, but it is downright odd. Honestly, these days 3/8ths is the smallest ID tubing we would even remotely consider using in a custom water loop. We are not alone in that opinion as it not only increases total volume of water but decreases static pressure of said fluid. So why did the (obvious) enthusiasts who designed this AIO compromise on this if they would not in a custom loop design? The most likely reason Artic carried over the same tubing (and excellent braiding on the outside of said tubing) is due to ease of use… and cost. One tubing for all the variants is just plain easier to purchase in larger quantities vs. multiple smaller orders. Remember, lower build costs means lower asking price, and this line as a very nice asking price. In other words, this is a touch disappointing, but not something that would make us buy one AIO over the other over.

wire - Arctic Liquid Freezer II 420 Review

On the truly positive side, the Arctic Freezer II 420 does also carry over the whole ‘one cable to rule them all’ philosophy. Arctic may not have been the first to hide all the fans’ cabling underneath the tubing, but they were arguably the first to take this to its logical conclusion by having all four fans and the pump be powered (and controlled) via one motherboard 4-pin fan header. Yes. All one need do is simply set up a ‘fan speed’ profile for this device in your mobo’s BIOS and the Freezer II will take care of balancing water pump vs. cooling fan(s) speed for you. All without needing to install and configure a dedicated software application. That certainly is a good definition of ‘user-friendly’ to us.

block2 - Arctic Liquid Freezer II 420 Review

As we have gone over in previous Arctic Freezer II reviews, we keep saying four fans and not three because Artic includes an excellent VRM cooling fan baked right into their custom waterblock. Once again they are not the first to try this, but certainly the first to actually understand the needs of overclocking enthusiasts… and then give it to them. Yes, that small 40mm fan may not move all that air (even at 3K rpm… it still is only a 40mm fan) but that couple CFM of air movement is down low and directed right at your motherboard’s VRM heatsinks. Heck, even motherboards without VRM heatsinks will notice a difference in VRM temperatures as this airflow is focused and will push air over ‘naked’ VRMs nicely.

The only hesitation some experienced users may have when hearing about this somewhat unique feature (e.g. ASUS’s RoG Ryujin has such a feature) is some variation on ‘what kind of amperage will you need to run all that?!’ or ‘that sounds like a mobo fan header killer to me’. The answer is… it is not as much as you would think. The gen 2 water pump Artic has created uses very little power. How little? That is hard to state as Arctic’s specs not only include it but the 40mm fan in its “1 to 2.7” watts of power usage rating. On startup both slowly spin up to speed and are usually only going to suck down a single watt of power. Worst case though, 2.7 watts at 12v is 0.225 of an amp. The three P14 PWM fans only use a nominal max total of 0.45A (or basically 1.8 watts each) and they too will not start out at full tilt boogie. Instead, they start at a mere 2.1volts and then work their way to 12v. This intelligent lowering of startup draw means that the ‘startup surge’ really is not a surge at all.

Put in simplistic terms, even ¾ amp header should be able to handle this device, and any 1A header will be happy running the Liquid Freezer II 420. Yes, this massive cooler veritably sips power. That is the upside to not having a USB integrated controller, or integrated LED controller, and no LCD panels to have to power via ‘fan’ headers… or any of the other goo-gaws that increase the MSRP and power draw without really doing all that much on the performance front.

block - Arctic Liquid Freezer II 420 Review
Moving on. The 420 variant of the Freezer II line comes with the exact same waterblock as the smaller variants. On the one hand, that certainly is not a bad thing as this may be a ‘block on the big side of things but it has the performance chops to justify its 78x98x53mm (WxLxH) dimensions. Put simply we like this block. We like it a lot. We like it so much that we really wish it have been designed around AMD’s 40x40mm “AM4” socket and not the Intel 115x/1200 37.5×37.5mm socket. That doesn’t sound like much of a difference but it is. Especially if you try and use these wonderful AIOs on AMD’s SP3r3 (aka sTRX4) socket and its 58.5×75.4mm dimensions (which we might add dwarfs Intel’s ‘HEDT’ 2066’s 52.5x45mm). This slightly smaller form-factor is one of the reasons that Artic had to redesign their AMD mounting setup to optimize the cooling of Ryzen 3 and 5K series processors. To be fair it is still excellent at cooling them, it just that Arctic are OCD about such things and wanted it to be as good as it could be. Also, to be honest, if they were going to redesign the block we rather see them make it ThreadRipper big and not just AM4 big… as if there was ever a form-factor crying out for cooling 64 cores of heat it was 420mm AIOs.

connectors - Arctic Liquid Freezer II 420 Review

The other minor nitpick we do is that if there was ever an AIO that cried out for upgradability… this is it. We have nothing against ‘old school’ 90 degree compression fittings perse. In fact, we do prefer them over swivel or quick connectors for certain scenarios. It just is those fittings mean that you cannot easily pop one off and add in a secondary run to say your water-cooled GPU and/or secondary radiator. Nor will you be able to add in a ‘water’ reservoir… or even flush, change, and burp the fluid every couple years. So, while yes we like this cooler – a lot – it could have been so much more. One with just a few minor tweaks could have taken on the likes of AlphaCool and their modular Eisbaer series. They did not, and instead squandered most of its true potential. As such, this is indeed a great sealed closed loop cooling solution, but one where a great opportunity for even more was missed. All for the sake of a quick disconnector and a bit bigger tubing. Now that is a shame.