Introduction, Specifications, and Pricing
A month less than three years ago, we saw our first Celcius cooler from Fractal. At that time, they took an average Asetek AIO, and bolstered the appearance of the head unit, used compressions fittings with wires run through them. Still, one of the significant changes over the typical Asetek offerings was that Fractal also included a fan hub on the radiator. At that time, our opinion of the Celsius coolers, more specifically the S36, was that we liked it, but we did take some points from it in performance as well as for value, but it was still awarded.
After a long absence, Fractal is back at it, this time using the latest generation Asetek models as the base for the build, but Fractal changed most everything else about the design! Opting for some of the most potent fans we have seen in a long time, and on top of that, they are ARGB PWM fans! Fractal even comes up with new tricks for the head unit. Where most are textured plastic, the coating here is matte and rubberized, much like what we see on mice!
There is a mirrored cover that has an ARGB LED ring around it, and in that same assembly is a switch to run one of two cooling options! We are just getting started with the list of changes and features of what makes the new Fractal cooler a stand out against those from NZXT or Corsair, but we do need to save some of this for the rest of the review, but we will get to it all at some point.
The series has evolved to what is now the Celsius Plus series, which contains a total of six new models. These models have options of a 240mm radiator, a 280mm radiator, or a 360mm radiator, within two sub-families. The first of them is referred to as the Dynamic, which does not come with ARGB lighting, and the fans differ from what we have. What we have been sent is from the second group, the Prisma line, and is the Celsius Plus S28 Prisma from Fractal.
While many AIOs that start at Asetek have not been great performers, with the specifications we have read, we have high hopes for this design, as it appears Fractal is giving the Celsius Plus S28 Prisma every chance they could, to make a run for the top of our charts!
Taking the information found in the reviewer's guide, we adapted it into an easier to read chart, which is seen above. Compatibility comes first in the list, and we understand that anything Intel is supported after, not including, LGA775, and the AMD support covers everything made after socket 939.
We quickly move to the copper cold plate with its pre-applied thermal paste on it, under the 45mm tall head unit. With the fittings included, the width and depth are 86mm and 75mm, respectively, but the main block body is only 62mm. Above the cold plate is the pump, and it will usually spin, up to 2500 RPM on a ceramic bearing, but there is a note to that speed. Should the liquid inside reach 60-degrees, the pump reacts by spinning at 3500 RPM until liquid temperatures reduce. The pump is powered with a PWM fan connection and is shown not to exceed 20 dB(A) while under operation, sipping 0.35 Amps over its 50,000-hour lifespan.
The tubing between the head unit is 400mm long, and it is low-permeability rubber with black Nylon braid covering it, which also has a fan power lead running along one tube, and the ARGB cable down the other, contained under the sleeve. The tubes connect to standard 90-degree swivel fittings at the head unit but use a new plastic compressions sleeve to capture the tube while allowing the wires to pass through as well. At the radiator end of the tubing, there similar sleeves around the fittings, which are on straight barbs, but the fittings do twist as well.
The fans that cool this AIO is Prisma AL-14 PWM ARGB 140mm fans. These fans will spin in a range of 500 to 1700 RPM on LLS bearings, and the max volume from them is shown to be 34.1 dB(A)! At full go, they deliver over 100 CFM per fan, with a static pressure rating of 2.38 mmH2O, while drawing just 0.18 Amps. The lifespan of the fans is shown to be double that of the pump, with a 100,000-hour rating.
The radiator, which is a high FPI aluminum model, measures in at 143mm wide, 30mm thick, and 324mm long, with standard 6-32" fan mounting threads.
Depending on which of the models you wish to pursue, prices will vary. As for the Celsius Plus S28 Prisma that we have in hand, Fractal is asking the same MSRP that we see many of the 280mm Asetek AIOs release at. That is right, to get something that looks entirely different than the average Asetek unit, comes with killer fans with ARGB support in the fans and the head unit, all of the features many strive for in an AIO. At $149.99 for the S28 Prisma, Fractal comes out with high hopes for this liquid CPU cooler, and we hope it does well, as we like to see more competition like this.
At the top-left corner, on the front of the box, we are shown that this is the Celsius Plus S28 Prisma, which is a pre-filled CPU water cooling system. The bulk of the area, filled with a view of the cooler in all of its ARGB goodness, with annotation at the bottom about it being designed in Sweden, next to the company address.
The top of the box delivers information in the form of features, listed in various languages, above the legal and company information. To the right, we see four stickers with the model number on three of them, and the serial number on the fourth.
At the right end of the box, we have the company and product name at the top. The rest of the panel is used for a graphic design made of bits of the Fractal logo.
The back panel starts like the front, with the name of the product at the top right, followed by the cooler taking up a lot of the room. However, this time there is a notation of a five-year warranty, and we see numbers in the rendering, which correspond to the five features listed to the right. These features are the tinted glass top with its six-LED ARGB ring around it, automatic temperature control, optional PWM mode, a combined ARGB and PWM fan hub, and the use of Prisma AL-14 PWM ARGB fans.
The left end of the box leaves the designs off this panel, this time opting to show the radiator in a pair of dimensional renderings. Below that, we see another mention of the included fans, the socket compatibility, and the company's online address again.
Even the last panel on the box has something to offer, and while we have seen the company name, product name, and product description a few times already, and with it this large here, there is no doubt as to if you have the proper cooler in hand.
Using recycled cardboard for the inner packaging, we find all of the parts and components separated in individual compartments. Plastic covers everything to help protect the finishes, but those little bits of the inner packaging stick to everything. Even so, the Celsius Plus S28 Prisma we received is in fantastic condition, without a scratch or blemish to be found.
Celsius Plus S28 Prisma CPU Cooler
The head unit of the S28 Prisma is built like a top hat, with a wider brim at the bottom, and a smaller section is rising in the middle. The top of the head unit is covered in a tinted glass panel with the Fractal logo to the right and is encircled with a ring of ARGB lighting from six LEDs. Unlike most other Asetek units, Fractal opted for a rubberized matte black finish!
Moving in a bit closer so we can make it our clearly, we find a notch in the side of the head unit. When you follow the groove to the glass top, you see PWM and AUTO. The top of the head unit can twist, allowing users to pick which control type is best for them.
On the edge of the head unit, we find a 3-pin plug, which would be at the bottom once installed in a chassis. The connection is for the ARGB cable located in the accessories, which needs the motherboard for ARGB signal to the cooler and is designed to work with various Sync methods from the different makers.
On the right side of the head unit, is where the fittings are. Starting at the top, we see the sleeve, captured with the plastic collars, which both have wires running threw them, and are connected to ninety-degree swivel fittings.
The underside of the head unit shows us that the hardware to mount it can be changed by twisting the bracket out of the tabs and sliding it off the unit. In the middle is the round copper cold plate, which has thermal paste pre-applied to save a step when it comes to installing the cooler. We do like the fact that we find no dirt or debris in this application of paste!
Removing the paste allows us to see the brushed appearance of the machining process, left in the copper. The cold plate is convex across its surface, but only slightly in the contact area, and bends more around the edge where the screws pass through it.
From the bend in the swivel fittings to where the tubes connect to the radiator is slightly less than sixteen inches in length, which is plenty for the average installation.
Between the rotary fittings found on the radiator, we have an exposed PCB with ARGB support at the back, and room for three PWM fans across the front. The hub allows the user to connect all of the bits to one area, which makes wire management of all of the cables a non-issue.
At the other end of the radiator, we see the standard Asetek sticker, which delivers the Fractal logo, model number, and serial number. More importantly, we see that this is the standard set of 27mm tick fins wrapped in a 30mm thick frame.
As we tend to see with an AIO, we find another dense radiator with the FPI count well into the twenties. Outside of that, everything is what you would expect from an Asetek cooler, even down to the rivets being exposed on the side covers and no custom nameplate.
Accessories and Documentation
Floating freely in the hardware bag, are the four components in this image. At the left is the 5V 3-pin ARGB cable, which connects the motherboard to the 3-pin connection on the side of the head unit. Next is the Intel backplate for use with LGA115X and LGA1366 motherboards. We then see the AMD head unit bracket, which uses a single screw to secure it to the motherboard. Lastly, we have a pair of adhesive wire management clips, to help deal with the fan wires.
Inside of a sealed packet, we found the rest of the Intel mounting hardware. To the left are the thumbscrews that secure the head unit to one of the sets of standoffs seen to the right of them. The standoffs in the middle are for LGA115X and LGA1366, while the set to the right is for LGA2011/-3 and LGA2066.
Another packet houses all of the fan screws and washers. Found inside of it are eight long screws for the fans, eight short screws to mount the radiator to the chassis, and a set of eight washers for the chassis screws. Inside of the bag to the right is the single AM4 screw, used with the head unit bracket.
The Prisma AL-14 PWM ARGB fans come with black frames, large rubber isolation pads in each corner, and use seven white blades, designed with added shaping and engineering to reduce noise while delivering strong static pressure. All while eliminating chop, cleanly scooping air through the radiator. On the front of the fans, you will find a white ring around the outside, but the hub is where the ARGB LEDs live, and the blades and ring reflect it.
From each fan, you will find they have two leads coming from a corner of the frame. One of them is the 4-pin PWM power connection, which can be routed to the fan hub. Each fan also has an ARGB cable, which is daisy-chain connections, so there is a male and female 3-pin connection on both. These ARGB connections should start from the hub, and then manage them from there.
The user guide at the left has every bit of information you will ever need to know about the S28 Prisma. Everything from a parts list, how to install, how to use charts on how the AUTO and PWM controls work, as well as delivering company information. To the right, we see the insert we always found in Corsair AIOs, where you are told to return the unit to the seller, not the manufacturer, should you run into an issue.
Installation and Finished Product
After sliding the corner bits inward to align with the LGA115X motherboard holes, we first installed the backplate. Outside of the threads in the corner bits, the entire plate is made of plastic, so that there is no chance of damaging the motherboard or shorting out against a component.
After flipping the motherboard over, we took the LGA115X standoffs and screwed them into the backplate. There are no washers here, but the standoffs run out of threads before the standoffs make contact with the motherboard.
The next step is to mount the head unit to the hardware, but we made sure to apply MX-2 since we removed the factory paste. The thumbscrews should be installed in an X-pattern to keep the pressure even, and you tighten these until you run out of threads. We also routed the 4-pin PWM wire for the head unit and routed the 3-pin ARGB cable so it would cause the least issues and be near invisible in the chassis.
Rather than take a bunch of images of how the head unit is taller than the RAM, or how it does not interfere with the RAM in any way, or how access to everything around it is unimpeded as well. We feel this image, and what follows shows all of it.
Before we attached the radiator to the chassis, we went ahead and did a bit of wire management with the fan cables. We were able to fit both of the sleeved 4-pin fan wires in here, and we could fit more if needed, should you want to try to clip in the ARGB cables as well. The instructions do not specify their installation, so use them as needed.
The gap between the top of the D-Frame and the motherboard is more substantial than almost any chassis out there, and we had no issues reaching with 400mm of the tube, and with swivel and rotary fittings, should the bends be more aggressive, both ends of the tube will adjust to relieve stresses. For those of you without ARGB control from your motherboard, this is the end of the road, unless you have another form of ARGB control. Fractal offers nothing for those on older systems without that feature.
Since our motherboard does not offer ARGB support, we dug into a box from another cooler and borrowed the ARGB hub from it to show the potential of the S28 Prisma. Doing so has a ring of color now shining from around the head unit, and both fans match the pattern we see on the head unit.
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.
At 60.25-degrees, using the S28 in PWM mode, we cannot say we are all that impressed with the near fifteen-degree gap to first place. When we look at coolers ranked higher, we were not fond of the Freezer 33, but at a fifth of the cost of the S28, it looks pretty good now! The specifications being what they are for the S28 Prisma, our hopes were much higher! For those that want to try the AUTO control, add four-degrees to the PWM results, and you will drop into the bottom seven coolers listed!
With the overclock applied, the S28 Prisma is now only eleven degrees from the top of the chart, but that 77.25-degree result of the Fractal, which ties with a $30 to $40 air cooler! The other side of the coin is that we are still twenty-two-degrees from the throttle point. Moving away from PWM to AUTO control, the temperatures jumped six-degrees this time, tying for last place!
As we do, we leave the overclock applied, and let the fans do their best at moving all the air they possibly can through the cooler, and see what is left on the table. With an additional 900 RPM and a ton more noise from the fans, we could only get another 3.25-degrees out of the S28 Prisma, which still leaves it near the bottom of the chart.
Noise Level Results
Under PWM control, with the stock load applied, the fans moved from 500 RPM at idle, to a whopping 540 RPM under load. While Fractal keeps the noise at bay with the 24 dB rating we have them at in our charts, we can see why thermals are what they are. Keep in mind that this is with the pump at 1660 RPM, and in AUTO mode, the pump only runs at 900 RPM!
For those out there who want quiet over performance, even with the overclock applied, the PWM curve kept the fans at just 775 RPM and 28 dB with the overclock used. The pump jumps up to 2083 RPM under PWM control, but on AUTO, the fastest we saw it spin was 1250 RPM.
Forcing 12V DC through the fans allowed them to top out at 59 dB, and with that enormous increase in noise and fan speed, it nets minimal gains to even deal with this level. We did notice that the pump turned at 2710 RPM at this time.
We now understand the point of the 3500 RPM option on the pump. The use of AUTO keeps the noise level between the head unit and the fans similar. Under PWM control, the loudest we got from the pump was 29 dB, but the slower it goes, the quieter it is. So with fans spinning at 550 RPM, with virtually no noise involved, the pump has to slow way down to coordinate with the fans.
In doing so, it allows the potential for a runaway condition, even if the fans are spinning nearer 800 RPM. Rather than blast your ears with the 58dB of noise from the fans in the last-ditch effort to cool things down, the pump spins at 3500 RPM until the liquid temperature returns below 60-degrees.
While it has been a long time since we last saw an AIO from Fractal, we do like what we see in this new model. Fractal has taken a step beyond the likes of Corsair and NZXT and upped them when it comes to the aesthetic game. Silence is of significant importance, whether looking at the Prisma Series we tested, or the Dynamic Series, and we do know that many do like a quiet CPU cooler. The 90-degree swivel fittings are something we feel all sealed AIOs should come with, but we have a new appreciation for the rotary fittings at the radiator!
The fact that the sleeve hides wires, and they can still twist without causing a bind is also a nice touch to add into the mix. Within the Prisma Series, like with our S28, ARGB lighting is the other big seller to the masses, and we feel that there are options with more and brighter displays of light, we have seen worse implementations as well, and this falls somewhere slightly above average in that department.
Sadly, though, with the sleek looking design and the long list of features to be found in this CPU cooler, we have to address the elephant in the room, well, two of them! The first thing we find to be lackluster is performance! At $150, we find this to be unacceptable. We get that the market dictates a price for the Asetek AIOs, but even the Kraken X53 and 73 beat this unit, and we railed NZXT about their performance. We are sitting here shaking our head as we write this, so much promise to fall flat on the one thing that is in the name of the product. It needs to be a cooler first, then add fancy stuff to it.
The second elephant has to do with the AUTO option of control, as we see no reason why with the lackluster performance we get with PWM control that we would be at the point to think that worse performance as an option was something to do. We understand the line of thought that they might be able to claim the quietest AIO in the game but to add a feature, then need a backup feature to allow the pump to spin at insane speeds to cool things down in the event of a runaway thermal scenario. Why? We are having such a hard time wrapping our heads around how this was a feature in the first place.
As it stands, at $150, outside of the cool factor of it being someone other than the big players in AIOs using an Asetek cooler, the facts stand as they are, and we have a hard time recommending this CPU cooler. From the onset, they had us, as we sat with high hopes that all of the features and options would come together is some cohesive manner, but after testing, we are left confused as to why much of this happened.
We get that Fractal wanted to be different, and set a trend that would set them apart from Corsair and NZXT, but if we were seriously contemplating a 280mm AIO right now, sadly, the Celsius Plus S28 Prisma would not be it! If you look closer at the charts, you can even see an ARCTIC solution there, whose review will go live later this month, and ARCTIC nailed it with an $80 for their 280mm AIO, just to shed more light on where this Fractal cooler sits in our mind.
The Bottom Line
With a long list of features, the Celsius Plus S28 Prisma may look amazing and be as quiet as it possibly can be, but the thermal performance and price will deter most from considering it.