Introduction, Specifications, and Pricing
As we said in the previous review, next to Corsair, NZXT has to be the second-biggest name in the AIO game, and have delivered us products in the past that were all the rage at the time, much like what they are attempting again in their newest X-3 series of sealed loop CPU coolers. Innovation is the name of the game with the new Kraken coolers, where it appears they have tried to think of everything that will benefit both NZXT as well as the end-user.
For those of you who have not glanced at the X53 review of the new Kraken coolers, let's bring you up to speed. NZXT took the latest AIO off the shelf at Asetek and cut, copy, and pasted ideas on it until they came up with what they feel is the next move to where the CLC game is going to go next. Everyone has low-noise fans these days, most companies offer RGB in some form on their coolers, tubing length has been gradually increasing, and many provide competent software suites to take full control of the systems. NZXT does much of that but also includes things like a rotatable top to the head unit, RGB lighting in the head unit, which then also branches out with HUE2 output signal to sync with other NZXT HUE compatible devices, and even increasing the viewable area where the ring effect and logo are displayed.
While we still have hopes to see the Z-3 Kraken coolers sporting a customizable screen on the head unit, we are here to see the largest of the X-3 coolers, the Kraken X73. Even knowing what we do about the X53 at this point, we still have hopes that the extra surface area that this 360mm radiator offers delivers the performance we expect it to. With another seventy or so CFM of airflow to drop the coolant temperatures, we would expect to see at least a couple of degrees advantage over the smaller unit. At this point, saying less is more, and we feel it is time to dive in and see if the NZXT Kraken X73 changes our outlook on this new way of offering an AIO to the masses.
With information found on the box and in the reviewer's guide, we put together the chart you see above. In it, we see that the head unit is 80mm in diameter, it stands 55mm, in height, is made with a copper cold-plate, and the housing around the pump and plate is made of black plastic. The pump speed is variable, starting at 800 RPM, and with software, you can top it out near that 2800 RPM mark. Power for the pump comes from a SATA power lead on the pump, drawing 0.3A over the 12V line.
The radiator of the Kraken X73 is 121mm wide, it is 394mm long, and it is 27mm in thickness. All of the components of the radiator are made of aluminum, and once assembled, it is painted black to match the rest of the cooler.
There isn't much to say about the tubing, but what we see is good news. The tubes are made from ultra-low evaporation rubber, which is sleeved in black nylon braid, and from fitting to fitting, it is 400mm long.
What NZXT calls the cap is referencing the top portion of the head unit. It is made of plastic as the "window" and brass for the "ring." The cap can be rotated to any of the 360-degrees but offers segmented stops every 30-degrees. Within the head unit, in a combination of the infinity mirror ring around the edge and the logo, there are none LEDs under your control. Part of that lighting ability exits the head unit in the form of a HUE 2 output lead with a proprietary 4-pin male connection at the end of it. The lead enables the X73 to sync with NZXT RGB LED strips or Aer RGB fans.
The fans get the most real-estate in this chart, and we see we get three Aer P120 120mm fans to cool the radiator. The fans can spin from as low as 500 RPM on up to 2000 RPM delivering 73.11 CFM of airflow. The pressure is good at 2.93 mmH2O, and 36 dB isn't obnoxious, but in the audible range. The seven blades and the hub spin on a fluid dynamic bearing, and requires 0.32A and 3.84W to get to those specifications. We did the math in the X53 review, and 60,000 hours is 6.8-years of life, which means as long as the pump holds out, the cooler should outlast the 6-year warranty, should something fail in that timeframe.
Compatibility, you can see that at the bottom of the chart, and to go out on our own, we will simplify things. LGA775 is no longer supported, but anything after that is for Intel. NZXT says they are AM4 ready, which also applies to AM3, and while they mention AM4 support, the bracket to make that happen does not come in the box.
The deciding factor, once you get past the initial drool on the desk stage, comes down to price! Where the X53 was set at $129.99, the 280mm X63 is $149.99, and we look to find that the new Kraken X73 is even higher at $179.99! To be blunt, at near $200 for an AIO, you are into open loop system territory, and for a sealed loop AIO, it better be the cat's meow!
Opting for a clean white backdrop, NZXT displays an illuminated image of the X73 in the center. Above it, we get the name of the cooler in bold black lettering, but the fine print is harder to read displayed in gray like that. However, the points were made. Here is the name, here is what it looks like. Turn the box to know more!
Doing just that, turning the box, we run into three versions of the specifications in multiple languages. Everything we covered earlier in the specifications is here, no shortcuts taken, you know exactly what you are getting!
On the back of the packaging, NZXT delivers four sections of information to look at. The first is about performance, covering the CAM control of the HUE 2 outbound lead, use of the seventh generation of Asetek coolers, and a bigger and brighter LED ring. Two of the following sections repeat this information while the last one touches on CAM software. If you desired to see what the cooler would look like installed into your chassis, they show that with the image to the right.
In eleven languages NZXT drops a features list on this end of the box. Things we haven't seen yet or already covered include the improved sync of the NZXT RGB accessories, NZXT CAM controlled pump and lighting controls, and that it is easy to install since the tubes are so long. The bottom covers requirements, which are Windows 10 and a free USB 2.0 port on your motherboard.
The inner packaging keeps all of the components from touching each other in transit, and the recycled cardboard has done a great job of that. We also like the secondary protective layers ensuring the cooler arrives in the best shape possible, which this has.
NZXT Kraken X73 CPU Cooler
Once free of the confines of the packaging, we took our first look at the head unit and found the cautionary sticker. We simply suggest you follow what the label says, and it is best if you leave this in place until the head unit is installed, as it keeps dust at bay, and also protects against any mishaps that may otherwise scratch the "window."
Under that sticker is a now larger viewable area, which increases the diameter of the ring LEDs behind it. The ring around the reflective plastic is brass that is painted black, and it rotates 360-degrees so that the now hidden NZXT logo inside of it is oriented correctly.
Swivel fittings are a must when it comes to an AIO, in our opinion, and we indeed have a pair of them, which drastically helps with the extra tubing you get. Beyond the fittings, the tube goes over the barbs, it is sleeved, and the plastic/rubber collar is stretched over it and allowed to compress it all.
Near the fittings, we find the connectivity points of the Kraken X73. The larger 10-pin connection supports all of the connectivity for RPM monitoring, power, and the HUE 2 outgoing lead. The smaller connection to the right is for the Micro-USB end of the USB 2.0 control cable.
Removing the plastic cover gives us an unimpeded look at the application of paste from the factory. Not only is the application done well, but again, we find no signs of debris, but it is still coming off of there.
Removing the paste shows us the circular machining marks that are left in the copper cold-plate. What is not as apparent is the slightly convex shape of the plate, highest in the center, to help with proper mounting pressure.
When checking the X53, we were spot on at the 400mm mark, but this time we see the tubes are well over sixteen inches, almost a half-inch longer on the X73 versus the X53. All the same, plenty of distance to make this AIO work in just about any case on the planet.
Helping to push brand identity even without anything running, NZXT presses its logo into the side covers of the radiator. This is done on both sides of the radiator so that any way you install the Kraken X73, it is easily visible.
So that you have a perspective of the thickness of the radiator, we grabbed an image of the end of the header, furthest from the fittings. On it is the product sticker with the model and serial numbers.
Looking through the fins, we find the X73 keeps the high FPI count we expect to see in many AIOs. Plenty of surface area with 22 fins per inch, and with nearly 80 CFM from each fan, we should see some gains in performance.
Accessories and Documentation
As part of the hardware kit, we pulled the AM3 and AM$ top bracket out, which can easily be swapped with the Intel one that comes on the head unit. For those on the Intel side, you will need this backplate to secure the rest of the gear, except for those running LGA2011 and 2066.
The four knurled nuts at re top-left are what secures the head unit, to one of the sets of standoffs. To the right are the LGA2011/2066 standoffs, with the universal Intel standoffs below.
The AMD standoffs may seem strange but are much more secure than any latch system. After removing the plastic ring around the motherboards CPU socket, these standoffs, at the wider end, screw into the factory backplate. The thinner ends use the nuts from the previous image along with the AMD top bracket to secure the X73 equally for both camps.
Hardware for the radiator consists of a set of twelve shirt screws to mount the radiator to the chassis. Next to them are four stacks with six washers in each stack. Across the bottom, we see twelve fan mounting screws, and washers should be used on both sides, but there are instances where you will need to make a judgment call there.
We find identical fans to that which are sent in the X53 box, just that this time there is a trio of 4-pin PWM powered RF-AP120-FP 120mm fans to blast air through that radiator. Rather than bulky corners or other means, NZXT uses a rubber cylinder in the fan mounting holes to fight vibrations.
On the left is the Micro-USB to native 9-pin USB 2.0, which connects the motherboard to the head unit. The manual in the middle covers anything you will need to know, from a parts list, detailed instructions, where to grab CAM, and what to do if an issue pops up. The cable on the right uses a tiny 10-pin clip to pass the SATA power to the head unit, allows for the 3-pin tack connection for the pump, and has the NZXT 4-pin male HUE @ outgoing lead as well.
Installation and Finished Product
When it comes to installing the X73, things start easy, as all we did was ensure the studs were slid inward and dropped the backplate into the holes in the motherboard. There is nothing that holds it in place, so you can either flip the board or hold the plate and board in one hand and install the standoffs with the other hand.
Either way, you decide to do it, this should be the result. Specific to this set of hardware, at this time, the backplate and standoffs are not locked into place, but that is intentional and will work correctly after the next step.
Be sure to apply the paste, if, like us, you removed the factory-applied stuff, and then set the head unit in place by aligning the standoffs to the holes in the top bracket. Once that is done, lock it all into place using the knurled nuts, taking the time to give equal turns in an X-pattern, and using a screwdriver to make sure that last thread is used.
Looking over the tops of the Patriot Viper memory, we can see roughly a third of the head unit behind it. This view also gives a perfect perspective for those looking to try to stuff NZXT AIOs into tiny cases. Not this specific one, of course, but the smaller models.
We thought it might have just been the X53 that overstepped its boundaries, but we find the same with the X73. There are options to correct the fact that the cooler presses against the memory, but we feel those solutions are an unsatisfactory answer to something that should not have been an issue in the first place. Two-stick kit users, you will not have this issue, it only happens when all slots are populated
Access to the 8-pin EPS power connection is wide open, there is room to all of the motherboard cooling solutions, and the wiring leaving at the top of the motherboard makes the most sense so that long runs are not needed.
Again, as we saw with the X53, taking the radiator well past what conventional cases offer for distance above the motherboard, we have our tube runs sweeping back and forth to try to keep the fittings level. You are going to have to work hard to find a case that this cooler does not have plenty of distance between the head unit and radiator mounting location to cause an issue with fitment.
Booting the system for the first time, we get our first view of the infinity mirror LED ring, and we also see the NZXT logo illuminated in the center. Both can be changed through Cam to static colors or use various modes and can be done so independently from each other.
If we were in a chassis with an inverted motherboard layout, we can leave the head unit installed as we have it, flip the motherboard 180-degrees, and with a twist of the cap on the head unit, we would see the NZXT logo right-side up. This is a nice feature that has been overlooked for years!
Test System Setup, Thermal Tests, and Noise Results
Chad's CPU Cooler Test System Specifications
- Motherboard: ASUS ROG Maximus VIII HERO (Intel Z170) - Buy from Amazon / Read our review
- CPU: Intel Core i7 6700K - Buy from Amazon / Read our review
- Memory: Patriot Viper 4 3000MHz 4X4GB - Buy from Amazon / Read our review
- Graphics Card: MSI GeForce GTX 1060 6GB OC - Buy from Amazon / Read our review
- Storage: Corsair Neutron XTi 480GB - Buy from Amazon / Read our review
- Case: INWIN D-Frame - Read our review
- Power Supply: Thermaltake Toughpower DPS 1050W - Buy from Amazon / Read our review
- OS: Microsoft Windows 10 Home 64-bit - Buy from Amazon
- Software: RealTemp 3.70, AIDA64 Engineer 5.75.3900, and CPU-z 1.77.0 x64
To see our testing methodology and to find out what goes into making our charts, please refer to our CPU Cooler Testing and Methodology article (October 2016) for more information.
Less than four-degrees out of first is an admirable showing for the X73 with the system at stock settings. We have to admit; we did not expect a two-degree improvement at this level over the X53. We hoped it would do that well, but we also had our doubts.
However, when we applied the overclock, that four-degree gap to first place is now closer to seven-degrees out of first. 72.75-degrees is still decent, but compared to the X53, it has lost some of that gap as well.
If you do not like your ears and want to try running the fans on the X73 balls out, you will soon find that the airflow and pressure are not the limiting factors. Adding a third more fan power to the system netted us a single degree of improvement.
Noise Level Results
During the stock run of testing, we saw that the fans topped out at 1000 RPM and delivered just 27dB to the room. Not the best result on the chart, but still well into the acceptable range for daily usage without it being dominant in the room.
We are okay with the 35dB results of the PWM controlled overclocked test session. The fans were turning at 1400 RPM. Certainly audible at this point, but behind a closed case door, or with a headset on, you will likely not notice it.
To get that last third of power from the fans, we had to enable DC fan control in the BIOS and tell it to drive the fans at full speed all of the time, which has these fans rotating at 2125RPM. It is then that we saw 52 dB on the meter, which is well beyond what most are comfortable with, and there are hardly any gains to be had to do so.
Additional notes to consider: All testing was done with the pump set to fixed mode at 100% resulting in a reported speed of 2777 RPM. Also, relying on my motherboard to do precisely what NZXT intended the fans to do may not coexist. Although, our last test put any of that to rest.
As we did with the Kraken X53 review, we do need to get it out there that we do appreciate what is going on in the newest to enter the lineup. We liked the oversized head unit's appearance and aesthetic fresh out of the box, and the fact that you can do all of the RGB things with the ring and the logo is something many expect to see in some form. Pump control via software is nice as well, and CAM can do many other things as well, but we are keeping it to how it pertains to the Kraken coolers.
The length of tubing is something we have wanted since AIOs became a thing, but up until a year or three ago, never seemed to be a concern, and now NZXT is taking it to a level past many others. We also like the idea of an AIO with a HUE 2 hub built-in, where those without motherboard RGB can still sync their accessories so that fans, the cooler, and LED strips are all doing the same thing.
We did bypass some of the issues, as we knew we would have this time to deliver our thoughts. On the one hand, we get that the HUE 2 hub is essential to NZXT and some users, but to do so means the lack of places to power the fans, and of course, then there is no software control of the fans either! Even if we had seen a Y-splitter or a daisy chain setup to use a single motherboard header would be reasonable, but to power three fans with PWM control, is a severe pain in the rear, on the motherboard we test with. It isn't always a matter of available fan headers, which is something that seemed to go over the designers' heads at NZXT.
Something else that went right past them is the fact that the increased display size also means that the head unit is bigger now when including the fittings into that distance. We may be in the minority, but I see people building PCs with all of the RAM slots full all the time, and the fact that the standard orientation of an AIO is no longer they7 way this is to be installed for those like us, it is odd and disappointing at the same time. Yes, we could have turned the orientation, but again, due to the USB cable, we are left with only two of the four possibilities on a full ATX motherboard. Imagine the issues on something like a Mini-ITX system!
There isn't a good side when VRM coolers are so close, the RAM side is out, and the GPU is just as close. The design limits its uses before you even open the box, and this, to us, defeats the point of developing a product in general. The last thing you want is to limit where it can go!
Even with the performance aspect, the basis of the cooler in the first place, while better than what we saw in the X53, is still hard to justify with the increased cost that comes with it. At stock, the X73 is an admirable solution, but if you are going with liquid cooling, it is typically for the hotter, faster chips, and being that is the reality we expect more from a cooler that nears the $200 mark! As we mentioned in the other review, if you just have to have one to try it out, the X53 is the most affordable option to try at this time, and overall we do not see the need for this much radiator for a degree or two here and there!
At $179.99, with the issues and reasons for doing said things not jiving with me the way it should, we cannot in good conscience lead you to believe that this is a good cooler or a sweet deal. It is innovative with some new tricks, cutting an essential feature in our opinion, and making the customer shell out for the privilege of dealing with how exactly you are going to use it when it complicates things to try to change it. We like the direction, yet, we feel that NZXT went too far too fast and forgot about some of the standards of what customers need from their CPU coolers.
The Bottom Line
Even though the Kraken X73 performs better than its little brother, the X53, the cost increase is not to near four times that of an air cooler that can outperform it, all while not showing the issues we saw along the way. Innovative or not, we feel they missed the mark!