[1aw/2ad/3ca/4] Raijintek Pallas CPU Cooler Review

Raijintek's Pallas is a new and inexpensive slim CPU Cooler aimed at the Mini-ITX segment; intended to compete with Thermalright’s top-of-the-line AXP-200.

Introduction

We recently tested Raijintek's Ereboss CPU cooler, which was also the company's first CPU cooler, period. That one was a massive tower cooler that left us with a good impression, particularly for low-fan RPM applications. We’re now taking a look at how Raijintek fares in the ITX CPU cooler market.

Raijintek is sticking with Greek mythology for nomenclature. Its first CPU cooler was the Ereboss, named after the ancient Greek god of darkness. The second one is named after a titan.

That choice of naming might raise eyebrows, since this heat sink is quite the opposite of a titan. Its advantage comes from a low, flat profile, which stands just 6.8cm tall with the fan already installed. So long as your motherboard can accommodate it, the Pallas becomes ideal for high-performance mini-ITX platforms.

Raijintek's sink offers six 6mm heat pipes, which should be sufficient to keep even enthusiast-oriented CPUs cool in confined spaces. And while it might look a lot like Thermalright’s AXP-200, there are some significant differences. The Pallas is 5mm shorter than the current segment leader. It also has more fins that are closer to each other and shaped differently. You should be able to find it for sale online for just under $40.

Packaging And Accessories

The Raijintek Pallas comes in a relatively small package. Its contents are kept in place by folded paperboard so that they don't bounce around. It's a truly efficient minimalist design.

The included accessories are similar to what you get with the Raijintek Ereboss. This isn’t surprising, since the two CPU coolers use the same backplate and retention frame that’s screwed in place. For the ITX model, two retention clips take the place of the large tower cooler’s four rubber fasteners.

This is also not the first time we’re encountering the low-profile fan with its 1.3cm-thick and 14x15cm tall and wide frame.

Design

The Pallas' sink is very different from the Ereboss that we recently tested.

Back to the Raijintek Pallas’ body. A direct comparison to Thermalright's AXP-200 shows Raijintek’s offering with a lot more fins. It has 69, whereas Thermalright employs 49. Naturally, then, the fins aren’t spaced as far apart. Surprisingly enough, the Pallas weighs less without its fan than the AXP-200.

The fins have a somewhat wave-like pattern and are interlaced in the center.

The cooler’s sides have notches to hold the fan’s retention clips.

The aluminum fins are bent in some places to prevent damage during installation. This is the only place where the otherwise-sturdy sink needs to be handled with care.

The Pallas is 6mm shorter than Thermalright's AXP-200. This is mostly achieved through the heat pipe design. Both coolers use 6mm heat pipes of identical length, but Raijintek’s stick out of the base a bit further, which shortens the part of them that bends up. There’s less space between the base plate and the cooling fins, which is to say that there’s less space under the cooler. We’ll take a look at how this affects practical considerations later.

In the height comparison above, Raijintek's Pallas is on the left, while Thermalright's AXP-200 is on the right.

The Pallas’ heat pipes are integrated cleanly with the cooler’s base plate. The contact surface with the processor is polished and plated with nickel.

The ends of the heat pipes are covered where they leave the cooler at the top. There’s another interesting detail here: the aluminum fins right above each of the pipes have little holes in them, which means that there’s a small air tunnel above each pipe. There are small knobs on the heat pipes themselves as well, increasing their surface area a bit.

We already know the bundled Aeolus fan from the Raijintek Ereboss. It’s slim at 1.3cm wide, and has a frame that measures 14x15cm. The red-and-white fan is fastened to the cooler with the help of retention clips.

Both the color scheme and the functional design are different from Thermalright’s competing offering. The fan as a whole is a bit more robust, but also a bit heavier. A cable length of 30cm is plenty for mini-ITX applications and should be ample in ATX-based systems as well. The Raijintek Aeolus has an RPM range between 650 and 1400, and it’s controlled via a PWM signal.

Installation

The Pallas’ installation mechanism is a carbon copy of the Ereboss’. It’s based on a backplate made of hard and sturdy plastic universally applicable to all processor interfaces. The advantage of this is that there are no parts isolating the backplate from the motherboard. However, this can also create problems on some boards due to the unconventional shape (see our compatibility notes below).

Screws with hexagonal heads are pushed through holes in the backplate and around the motherboard's CPU interface. The screw heads sit in fitting indentations in the backplate. On the front, plastic spacers are screwed on.

Next, the included retention bars for the cooler, which are different for Intel and AMD systems, are fastened in place with thumb screws.

Finally, a crossbar is fastened to the cooler and screwed to the retention bars. The screws are easy to reach through holes in the cooler.

The crossbar has a pair of protrusions that snap into place in two holes in the cooler’s baseplate. This keeps the cooler from sliding.

Notes On Compatibility

Similar to the Ereboss, installing Raijintek's Pallas in 90 degree steps is only possible on Intel systems. Of course, this typically isn't an important distinction for coolers that blow down onto your motherboard, though.

The backplate can cause problems with ITX motherboards. If your board of choice has surface-mount components behind the CPU interface, in a worst-case scenario, the Pallas could crush them. You'll need to check for compatibility before trying to seat the backplate. This usually isn’t a problem for the larger form-factor motherboards, but, unfortunately, it’s a common issue for smaller ones.

Raijintek's Pallas fit loosely on an Asus H87I-Plus motherboard. There were no problems with it on an ASRock B75M-ITX, though. It should be noted that the Asus board does diverge quite a bit from Intel’s reference design.

Raijintek could avoid these problems in many cases if it had the backplate touch the motherboard in just a few places, as opposed to it lying flat. This could be achieved by using additional spacers between the backplate and motherboard. Thermalright uses that sort of configuration for many of its CPU coolers. In talking to Raijintek, the company promises to examine this possibility and upgrade the Pallas if it works out.

Memory modules without heat spreaders and those with smaller ones that don’t extend above the upper edge of the PCB by more than a millimeter can be placed under the Raijintek Pallas.

How We Tested

CPU Cooling - Overclock and Normal Performance Settings  
ProcessorAMD FX-8350 @ stock settings (normal)
AMD FX-8350 @ 4.4GHz, 1.4325V, LLC=Medium (overclocked performance)
MotherboardGigabyte 990FXA-UD7 (BIOS F10)
RAM1x 4GB G.Skill (DDR3-1333 CL9)
Graphics Card
XFX Radeon HD 5450 (passive)
SSD60GB Kingston SSDNow V+ 200
Power Supply
Xilence XQ Series Platinum R4 (1000W, semi-passive)
PC Case
Cooler Master CM Storm Stryker
Case Fan Front and Back: 1000 RPM
Case Fan Top: 900 RPM
OtherAqua Computer Aquaero 5 LT (firmware 1027)
Arctic MX-4 (thermal paste)
Operating System
Windows 8 Pro 64 Bit  (Version: May 2013)

In order to measure the processor’s temperature, it first endures 60 minutes of Prime95 with custom settings, heating it up. Then, its core temperatures are measured for 10 minutes. Finally, all of the temperature measurements across the entire interval are averaged.

This procedure yields more accurate results than recording the temperature at just one point in time. Unfortunately, the processor’s internal sensors provide relatively imprecise values, since they exclusively use whole numbers. This means that the results might have a somewhat higher measurement error.

Noise measurements are conducted with an open PC case from a distance of 30cm perpendicular to the center of the CPU cooler. Don’t panic after looking at the results; a closed case and a more reasonable distance from it will significantly reduce the coolers’ noise level. A greater distance would have meant that ambient noise would play a larger role, increasing measurement error.

We’ll adjust our benchmark system for ITX-oriented CPU coolers soon so that we can test them in a fitting PC case. Even without a purpose-built platform, Raijintek's Pallas turned out to be a strong contender in our tests. It didn’t just manage to complete our usual 125W CPU suite without breaking a sweat, but it also left us amazed after seeing the results of our overclocked 180W workload.

It’s not every day that a diminutive 6.8cm CPU cooler, which was designed for cramped spaces in tiny PC cases, can take on established tower coolers priced at up to $50. We didn’t even trust our results at first, but several more test runs didn’t change them.

The Pallas’ main competitor proved easy to find: it’s the Thermalright AXP-200, which is our go-to cooler for extremely high-performance systems that are supposed to be built with a very small form factor. Alternatively, we use the Deepcool Lucifer, which operates on a similar level as the HR-02 Macho, and the be quiet! Shadow Rock 2, which might not be able to provide quite the same cooling performance but has a leg up on the competition when it comes to noise level.

With the exception of the Thermalright AXP-200, we’re putting Raijintek's Pallas up against supposedly stronger tower coolers in its price range. Again, the results turned out to be a big surprise!

Stock Performance

Looking at the results achieved with a common 125W stock CPU, it quickly becomes clear that the Pallas is, in fact, a tiny titan. At maximum RPM, it beats the Thermalright AXP-200 by three degrees Celsius. The two CPU coolers perform about the same at 1000 RPM.

These results can be explained by a difference in design. Thermalright's AXP-200 has fewer cooling fins that are spaced further apart from each other, which causes it to lose less performance at lower fan speeds. The Pallas, on the other hand, capitalizes on higher air pressure with its many tightly-packed aluminum fins. Its 14cm fan also spins approximately 100 RPM faster, resulting in a lead over the Thermalright AXP-200.

Raijintek's Pallas is able to compete with the tower coolers surprisingly well too. It beats the huge be quiet! Shadow Rock 2, which weighs more than a kilogram. It doesn’t manage to keep up with the Deepcool Lucifer, but comes in two to five degrees Celsius higher. It’s a fraction of the size, though.

Overclocked Performance

Raijintek made a point of telling us that the Pallas would be able to cool a 180W processor before the company shipped us one. This usually earns a skeptical reaction from us as we make a mental note to run the benchmarks in spite of them probably being a waste of time.

In these cases, the CPU cooler is usually unable to make good on the manufacturer's promises. Raijintek's Pallas proves to be the exception. It doesn’t just keep our overclocked AMD FX-8350 cool at maximum fan RPM, but it even does so after slowing its fan down. The heat sink's direct competitor, Thermalright's AXP-200, fails both of these tasks. The same goes for be quiet!'s Shadow Rock 2.

It does get tight at 1000 RPM with a measurement 45.8 degrees Celsius above ambient temperature, which might not be quite enough if your air conditioning unit breaks in the middle of a hot summer. At the maximum fan speed of 1423, this number drops to 39 degrees Celsius. That's only five degrees higher than Deepcool's giant Lucifer.

Noise

High cooling performance achieved over a small surface is always accompanied by more noise. The Pallas’ maximum fan speed is 1423 RPM, which is faster than the AXP-200’s 1295 RPM ceiling. Those speeds result in noise levels of 45.5 and 44 dB(A), respectively. At 1000 RPM, the Thermalright cooler is still quieter than Raijintek’s offering by 0.5 dB(A). The newcomer comes in at 39.7 dB(A) after slowing down its fan. This doesn’t have to be the last word, though. Its fan can be further slowed all the way to 650 RPM via the PWM signal.

Raijintek's motor noise is noticeable in open or mesh-heavy PC cases; there’s some room for improvement in this area to quiet things down. Unfortunately, there’s (literally) less room for these improvements than there would be for a 2.5cm-thick fan. Then again, the AXP-200’s fan isn’t completely quiet either.

In spite of using the same fan as Raijintek's Ereboss, the Pallas’ results are somewhat worse than its sibling’s. One of the reasons for this is the different position of the downward-facing fan in relation to the measurement microphone. Using a different fan isn’t possible without major alterations either, since the included retention clips are specifically designed for low-profile fans. Raijintek doesn’t include an installation frame for larger fans like Thermalright does with its AXP-200 either.

Conclusion

Raijintek achieves the seemingly impossible with its Pallas low-profile CPU cooler. The company produces a brand-new entry in the mini-ITX-specific category that beats our previous recommendation, Thermalright's AXP-200, in several key areas and costs less to boot. Numerous small optimizations give it better performance and less height at the same time.

The Pallas’ higher number of aluminum cooling fins, which are also closer to each other, lets it convert its fan’s higher maximum RPM straight into more performance. The more you slow the fan down though, the more that advantage shrinks. This is due to the different underlying design concepts of the two CPU coolers.

In any case, the bottom line here is that Raijintek's Pallas can handle an overclocked 180W CPU. Performance reserves like these might not always be necessary, but they’re certainly impressive. Enthusiasts who’d like to overclock their processors in a confined space and want to stick with air cooling will find the right tool for the job with the Pallas. Its reserves also make this heat sink a true all-arounder. Even some tower coolers with massive surface area can’t handle our overclocking scenario.

The Pallas’ build quality can also be recommended without any reservations. Thermalright's AXP-200 sports a smaller number of thicker fins, making the sink seem more solid and robust. It also includes the option to use a full-size fan, fares better in the looks department and is quieter. Finally, Thermalright’s backplate has better compatibility with ITX motherboards. Raijintek might take care of this shortcoming in the future, though.

Those factors aside, the Pallas is a clear winner when it comes to height. Standing 6.8cm tall (including the fan), it beats the competition by 0.5cm.

Bottom Line

This year’s first real surprise in the CPU cooler category is here: the Raijintek Pallas. It takes the crown, becoming the most powerful mini-ITX-specific CPU cooler. That’s not all, though. It has the unique ability to cool overclocked 180W CPUs that even some tower coolers can’t handle, making it an option for use in larger systems as well.

At $40, the Pallas is also less expensive than its direct competition. The only caveats are a backplate that’s not compatible with all mini-ITX motherboards and the missing option to install a full-size fan. Neither of these change the fact that Raijintek's Pallas is the new reference for cooling performance in the low-profile space.

MORE: Best Gaming CPUs For The Money
MORE: How To Build A PC
MORE: All CPU Content

MORE: All Cooling Content

Kai Tubbesing is an Associate Contributing Editor for Tom's Hardware Germany, covering Cooling.

Follow Tom's Hardware on Twitter, Facebook and Google+.

Create a new thread in the UK Article comments forum about this subject
This thread is closed for comments
No comments yet
Comment from the forums
    Your comment