Antec KUHLER H2O 620 Liquid Cooling CPU Cooler Review

Antec pairs with Asetek and brings their version of all-in-one water cooling to the scene.

Manufacturer: Antec
11 minutes & 46 seconds read time


Antec KUHLER H2O 620 Liquid Cooling CPU Cooler Review 99

Antec has been in the business for a long time. In fact, they are celebrating their silver anniversary. That's right, Antec brings twenty-five years of experience to the table! With this sort of history, they know a good idea when they see one, and of course they saw what all the rage is in all-in-one water cooling loops. Corsair and CoolIt have made good amounts of money off of this concept, and now Antec figures it is time for their share of the market. I assume this is where the call went over to Asetek from Antec.

Pairing up with Asetek, the same manufacturer of the Corsair H50 and H70 coolers, Antec takes ideas from both and made a couple of changes. With the new line of KUHLER coolers that hit the floor at CES, this was one that I know was in the plans at that time, but I can't recall if it was in the videos or not. Anyways, in the most basic sense, Antec took the head unit from the H70 and the radiator from the H50; got rid of the annoying tube covering, added a single fan, and are offering it up under their own label with the KUHLER H2O 620 moniker.

With many other versions of this exact idea, at last count still being produced, it makes this five. Both from Corsair have taken on almost a cult following, while the CoolIt offers better mounting; it seems like they fall in second. So that leaves Antec to make a push and see if there is some room for them to claim a stake in this market. Hopefully by the end of this review I will find something about the new Antec unit that will set it apart from the others we have already seen and tested.

Specifications, Availability and Pricing

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Since the specifications given of the pump and head unit are very limited and all I can give is dimensional information on the radiator and tubes, I figured I would start this a little different this time. The top image is some in-house testing from either Asetek or Antec. This testing is done with a stock cooler, the 620 and a "first gen liquid cooler". Now I'm not exactly sure which cooler that refers to; if it is the H50, or one of Asetek's original creations. Either way, it does show marked improvement over the older tech.

To describe the unit I will start with the head unit. This head unit is the thinner version of the two Asetek made for Corsair, and from what I can tell from the outside it uses the same copper base with thin channels the water passes through to transfer the heat. Incorporated in the head is a pump that is powered with a plastic impeller. The casing surrounding the head unit has both the Antec and KUHLER names, and keeps the ninety degree swivel fittings to give better access to the processors alignment. From these adapters, there is black rubber tubing with an 11mm outside diameter that make their way to and from the radiator. Gone is the hard plastic outer wrapping that Corsair uses, and this should make some tough installations easier.

The radiator is taller than it is wide, but you will need an area of 151mm by 120mm to install this cooler easily. The 120mm fan that accompanies the kit is capable of speeds from 1450 to 2000 RPM. This speed can be left to the BIOS and PWM to control the temperatures, or with some BIOS' and with others software, you can tune the fan to stay silent, or be louder and run full speed all the time. The fluid that transfers the heat is an eco-friendly solution that has an anti-corrosive additive to allow for the dissimilar metals in loop. With any good cooler it needs to offer full compatibility, and Antec made sure and offers usage with all the latest AMD and Intel sockets.

Now we need to get to the important part; pricing. While there are deals from time to time that make the H50 a steal at $50 when they go on sale, most of these creations are going to run you in the $60 to $100+ region depending on brand and options. Antec is releasing the KUHLER H2O 620 with a MSRP of $69.95 when it does hit shelves. Going through Google Shopping, results are mixed. Some e-tailers show stock, some say limited stock, while others are showing no stock, but are still listing it. Most of these shops are also pricing well above the MSRP, so if you do want to get the latest all-in-one water cooler, look carefully for the best deal.


The Packaging

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On the front of the KUHLER H2O 620 there are a lot of things to point out. First is the new Antec logo with the silver 25 following their name. Next there is a large image of the 620 fully assembled, and it even shows the direction of airflow; this time it flows outside the case. Antec also covers the compatibility, its quiet nature, the quick installation, and zero maintenance.

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The same chart I pulled to display in the specifications is also displayed on the side of the packaging. Tested with one of the most powerful i7 processors, these results are what you should expect as worst case scenario. Most systems will run cooler than this testing shows, unless you are running an i7 980.

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The back is topped by a brief statement about the H2O 620 in blue text, which gets repeated in five other languages. Beneath this are four images with explanations of each feature. At the very bottom, just in case you happen to have any issues, Antec places the contact information here for easy access.

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The last panel holds specifications for the sizes of the radiator and the fan. It also shows the speed of the fan, the contents and makeup of the coolant, as well as the weight of the unit fully assembled. At the bottom you will find a multi-lingual checklist of included parts.

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As you go to open the box, Antec not only shows the three main features again, but also offers an image of a typical installation inside of a case.

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The unit comes disassembled inside of a recycled cardboard tray. To keep anything from scratching the components inside, a thin layer of dense foam is placed on the top to protect the components underneath.

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The tray is well compartmentalized and offers a snug fit for the radiator and head unit. The fan and hardware are freer to move about, but their size keeps them in the center compartment during transit. Antec did a fine job of delivering me a product in perfect shape.

The Antec KUHLER H2O 620 Cooling CPU Cooler

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Pulled right out of the box, you can see there are still a couple of protective measures taken to protect the head unit. Both a bag to keep scratches away and keep the logos in pristine shape, which along with a hard plastic cap over the base plate protects the base and its pre-applied TIM. Outside of the fan installation the unit comes as a complete system and only leaves the mounting of the head unit and which side of the radiator to place the fan as choices during the install process. The rest of the cooler comes as you see it here, just that it is no longer nestled in the compartments.

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The radiator utilizes a high FPI, or fins per inch count. Radiators with tighter fins are more efficient at ridding the radiator of heat, but require a pretty good fan to achieve good results. As with most of the other all-in-one kits, there is nothing new to the radiator design.

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Looking at the radiator from a better angle, it is much easier to see just how tight the fins are placed. Something you may not have noticed is that the 620 also comes with mounting holes on each side. This allows you to choose the side for the fan depending on fit in some cases, and will offer you the option to add a second fan later.

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Something a bit new to me is the attachment points on both the head unit and the radiator. As you can see, there is a collar on the end of the tubing, but it is not a clamp. From what I can tell the hose is likely stretched over the fitting, and then the collar gets slid over the top for security. I don't think it is an end that clips onto the barbs.

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Between the head unit and the radiator there is near twelve inches of tubing to offer room to hang the radiator in various locations. Even the wiring included is the same length giving you plenty of options for orientation and where to get the source of power.

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The top of the head unit has the housing labeled with Antec and KUHLER H2O 620 printed on the right and the bottom respectively. The round cap in the center is what I believe may be where the unit gets filled. If you pop off this cap you are greeted with coolant; that's how I came to that conclusion. I really can see no other use for it.

The Antec KUHLER H2O 620 Cooling CPU Cooler - Cont.

The Antec KUHLER H2O 620 Cooling CPU Cooler - Continued

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Back to the head unit, I found the same 90? fittings the H70 had. This time however I found a large amount of grease-like material around the fittings. I went back to look at the H70 and it did have similar grease, but the excess was cleaned prior to shipping, so it was much less noticeable. The tubes end in the same fashion as they did on the radiator end, with a similar collar instead of a clamp.

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Off of the top of the head unit there are two wire leads. One has a 3-pin male connection to power the fan. The right wire has a 3-pin fan connection to power both the pump and the fan with one easy connection to the motherboard.

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If you are going to send a cooler with compound pre-applied, you might as well protect it very well. The plastic cap has notches on it and needs unscrewed a bit to release the tabs so you can remove it. It serves a very good purpose and is something I'm glad wasn't lost with Antec.

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The pre-applied compound is spread on the base plate very thinly and with a textured pattern. The area provided does cover the full IHS and is plenty of compound to get you under way when you get your own H2O 620.

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Removing the paste, I can see the copper base is milled in a circular fashion, but the milling work is taken to a finer level as was the bases from Corsairs coolers. This plate was flat in the middle and only deflected from a straight edge in between or outside of the ten screws holding the copper plate onto the head unit. I think we covered just about everything at this point, so let's move on to the hardware and instructions.

Accessories and Documentation

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Packed in the box right next to the fan you will find a large plastic baggie with all the hardware you will need to mount this into any AMD or Intel system listed on the box.

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Floating freely in the large bag there is both sets of back plates as well as the top of the socket hardware. The AMD kit on the left and the universal Intel mounting on the right keeps the same mounting hardware at this point, as did the other Asetek solution.

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Inside of a pair of smaller bags you will locate the rest of the hardware needed for a full installation. The left bag contains four long screws for mounting the closed corner fan to the radiator, four medium lengths and in this instance, three short screws for mounting the radiator to various cases. There is also a set of four washers to be used for the screws going through the fan; this will ensure you shouldn't puncture the radiator during assembly.

The bag on the right contains the blue Intel adapter and the green AMD adapters that get snapped into the top mounting rings. Along with those you will find the mounting screws, along with "nuts" that go into the back plates. To help with spacing as well as holding the back plate in place, there are two foam strips with tape on both sides so you may secure the plate to the motherboard.

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I figured I had better show the fan at some point, and without further ado here it is. Antec went with a seven blade, 120mm, all black fan to go along with the cooler. While I didn't get a maximum CFM rating for this fan, my guess would be around 40 CFM at lower speeds, and at the full 2000 RPM, I would venture to say the fan is in the 70 to 80 CFM range.

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The instructions are very clear and well illustrated. On the front you get a full parts check list, and it seems I got a lot of extra screws, or they forgot to add the smaller ones to the list. At this point you decide if you are using the AMD or Intel hardware and get underway. This side will get you through the first half and you will have the back plate installed to the back of the motherboard.

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On the reverse Antec takes you through the rest of the steps. Mounting into the case, mounting the head unit, and even how to plug the unit in are all covered. There is no reason you should have any issues with installation, unless of course the radiator doesn't fit where you want to place it.

Test System & Testing Results

Test System & Test Results

TweakTown uses a different method for testing CPU heatsinks which allows for an even playing field across all product tests. We feel that by using the same ambient temperature and strict lab-like testing procedures we are able to accurately compare one product to another. More information on our testing procedure can be found in the T.E.C.C. article here.

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With idle testing completed I noticed that only the H70 is cooler at this point. Antec pulled ahead of the CoolIt ECO and the Corsair H50. Seems the component combination Antec chose from Asetek is a good match so far.

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In load testing the results are much the same of the four in the chart. What I did notice is that the Antec made some headway towards the H70. In fact, testing showed an almost even performance.

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Sound level, while not "quiet" like the box insinuated, it is below average as far as noise output goes. 46 dB is respectable for the amount of cooling the KUHLER H2O 620 is capable of.

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At full load the 620 jumped right on up to the louder fans we have tested. 68 dB isn't screaming loud, as the Frio OCK set a new record there, but you will be able to notice a hum coming from the case with the use of the 620 under full load.

Final Thoughts

While Antec is a bit late to the all-in-one water coolers, they are making a pretty good entry. This unit is able to slightly outperform the direct competition while keeping a very close second to a version that includes two fans and a thicker radiator. What's there not to like? I mean if you are going to enter the market with a cooler we have seen in other variations, you've got to bring it to the table, or you might as well not bother showing up. Antec took full advantage of what Asetek had to offer and delivered a very efficient variant in the KUHLER H2O 620.

Things I disliked about the cooler are minimal. It seems the more I use the hardware the easier it gets, but the system is pretty complex, and if you make a little mistake like placing the adapters in the top ring backwards, you will soon have to disassemble most of your work to correct the issue. That's really all I have. Things I would want from Antec, since the 620 performed so well...well, I would like to see a two fan version of this, or maybe Antec will take the lead and make a dual radiator version available to the masses. I know CoolIt will do it, but it seems to be custom orders only; let's see it done for the masses.

Is this the top dog in all-in-one coolers? Not exactly, but very close, especially with the lack of dissipation area and only half the fans of the H70. So it all comes down to the price tag. With the other versions already taking the market by storm, they are able to lower pricing at this point. As a comparison, lists the H70 for $109.99 and the H50 for $75.99 currently. With the results the Antec KUHLER H20 620 was able to produce, that $69.95 US dollar MSRP doesn't sound so bad anymore, does it?

If you want one of the better of the all-in-one, easy to use water coolers, I would suggest the Antec has more bang for the buck than does any of its competition. That is why I award it the Editors Choice award and rated it accordingly in the scores.

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Chad joined the TweakTown team in 2009 and has since reviewed 100s of new techy items. After a year of gaming, Chad caught the OC bug. With overclocking comes the need for better cooling, and Chad has had many air and water setups. With a few years of abusing computer parts, he decided to take his chances and try to get a review job. As an avid overclocker, Chad is always looking for the next leg up in RAM and coolers.

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