Introduction: CPU Cooling over the years

If you want to go straight to the gritty details of our test today, feel free to skip to the second page. If you want to learn a bit of history regarding air CPU coolers over these last years, stick around.

CPU manufacturers are consistently trying to squeeze more transistors in ever smaller packaging; there was a time when you passively cooled your CPU with a very small aluminum heatsink, only a few centimeters tall. This was back in the 386/486 era; since then the thermal management of CPUs has been more and more challenging as the heat output rose. First we saw manufacturers put small 40mm fans on their aluminum heatsinks to keep the processor running cool.

The Pentium series really got the ball running, when the Pentium 3 was released there were already a few third manufacturers producing custom air cooled heatsinks. But it was AMD first Athlon CPU which caught the attention of the enthusiasts, especially the socket A version of the AMD CPU had quite a nice selection of retail coolers available which allowed you to increase the performance of your processor and still keep it running cool. Noise wasn’t much of an issue back then for most users, strange as it might sound to some, the first high end CPU cooler I bought was a GlobalWin FOP38:


(photo courtesy of Digit-Life

Made to fit both Intel P3 (Socket 370) and AMD K7 (Socket A) the design is not very advanced compared to today’s models. It was made entirely from aluminum with a series of thick fins extruded from the material. The real show stopper was the fan GlobalWin included… a 60mm Delta fan with an insane rotation speed of 6700rpm. I have not yet encountered a more ear piercing cooling fan as this little monster; it delivered outstanding performance, no surprise there, the real kicker was that this cooler was sold worldwide and was in PCs of enthusiasts who did not really complain about the noise. Sure ordinary folk thought we were crazy. I remember firing up my AMD Athlon powered system on the 2nd floor and a colleague of mine who was in the kitchen asked if I started the vacuum cleaner… the kitchen was on the ground floor.

So it seems that at the beginning of third party cooling products manufacturers had free reign about what fan and material they used, as long as the product cooled the CPU better than the competition their product would sell. GlobalWin was challenged by Alpha and Swiftech when the AMD Athlon became more and more popular; these new contenders brought products to the market with a copper base and aluminum fins. You could fit larger fans, up to 92mm and this gave them the edge.



The Athlon XP from AMD was then launched to do battle with the Intel Pentium 4. Both these CPUs offered quite a thermal challenge for then current heatsinks. And so new product version were released by Swiftech and Alpha and they traded placed at the top… until a new contender appeared on the scene. A new upstart in Taiwan called Thermalright was producing copper heatsinks, made from a large series of fins soldered to a flat copper base. The SLK series was born and it left the competition in the dust for several months to come.



Coolermaster, Zalman, Coolink and other companies jumped on the third party heatsink bandwagon as it started rolling faster and faster; enthusiasts were in for some good times, with many different heatsink designs and copper/aluminum ingredients the prices came down and none enthusiasts started paying attention to those “blocks of metal one put on a CPU”. They were not interested in raw performance, they didn’t even know what overclocking meant. Both AMD and Intel reference heatsinks were average at best and not very silent. Zalman was one of the first to actively focus on silence over performance and their CNPS “flower-design" coolers popped up on the shelves local PC stores.



The Pentium 4 Northwood revision was introduced and the scales started tipping towards Intel with more enthusiast buying this new CPU which really scaled well, overclocking with air cooling reaching 100% were previously unheard of, but this CPU could do it. With extra vcore and higher speeds the temperatures also increased exponentially. Thermalright released their latest product, changed the series name and took the performance crown; the SP-94 (P4) and SP-97 (AXP) were their first heatsinks featuring a new technology to help transfer heat from the CPU. Heatpipes became popular overnight.



As far as technology heatpipes are as far as we’ve come today; no other technology which improves on heatpipes has been commercialized for use with air cooled heatsinks. Since the SP-94 the size of heatsinks has grown to accommodate the continued increase in CPU heat output. The Athlon 64 series when overclocked offered quite a challenge to cool down without noise and it took quite a bit of aluminum, copper and heatpipes to get the job done.

Amongst the new slew of products was one from a Japanese company called Scythe, their first products included a custom Heatlane technology, similar to heatpipes but it could be bend out of the shape better without performance loss, the downside was the cost of the technology. Their Shogun heatsink was the last one with the Heatlane technology, it supported 120mm fan for cooling and paired with either low noise or fast fan performance was stellar… but the costs were very high for both manufacturer and retail channel.



Than 3 years ago Scythe introduced their Ninja and low noise cooling would never be the same; this huge heatsink could fit up to 4x120mm fans, but was in fact designed to be used… without. The massive surface area and low density of the fins allowed the Ninja to keep the CPU cool inside a case which had at least one exhaust fan.



For the last three years there have not been a lot of alternative choices for the Scythe Ninja when it came down to completely passive cooling; Thermalright brought out a HR-01 unit which did ok but could not match the performance of the Ninja. Today we take a look at a new product from Scythe and a newcomer from Coolermaster which is marketed for fanless operation. Let’s take a closer look to see if these product can bring us back to the 386/486 days of passive cooled CPUs ->

Scythe Ninja CU

The original Scythe Ninja was launched more than 3 years ago, since then Scythe has released several revisions to perfect the manufacturing process and mounting system for the new platforms. The basic design however has remained pretty much the same, a limited series of aluminum fins which are approximately the size of a 120mm fan are held together by no less than six U formed heatpipes; these heatpipes are joined together in a copper base large enough to cover the latest AMD and Intel processors.

At Cebit 2006 Scythe demoed a copper Ninja CPU cooler but we were told that it would not be available in retail due to the increased cost and less than stellar performance improvement over the normal version.

The original version will set you back approximately €35 (PC-Cooling.de) while the new full copper version costs ~€55 (BytesAtWork), that's quite a premium you have to pay; in that regard Scythe was right that the Copper version is not very cost effective. But the public demand was large enough for them to produce a Copper version of the Ninja in larger quantity. Today we’ll find out if its performance is worth the extra cost.



The packaging is quite clear but a bit logo heavy; still it gets the message across of what the product is and what it is capable of.

Specifications



Yes the Ninja Copper passes the magical 1000 gram weight limit, not a lot of CPU coolers out there even come close to this. The included fan is build for silence with a rotation speed of only 800rpm at 12v your system will be very quiet.

The Scythe Ninja supports all current AMD and Intel platforms (AMD S754,S939,AM2, AM2+ - Intel S478, S775).

In the box



For your money you get:

Scythe Ninja Copper Cooler with 6 heatpipes

Low noise 120mm fan with 3-pin power connector.

Detailed installation manual

Mounting gear for all platforms

A small bag of thermal paste

A pair of clips to install the fan onto the heatsink

We would have loved to see an extra set of clips as the Ninja heatsink has enough mounting points to have multiple fans installed, only thing holding you back is room inside your case. The fan has no PWM support, PWM is quite popular nowadays on both AMD/Intel platforms and allows for better automatic fan speed control through the BIOS. But seeing as the fan is running at only 800rpm at full speed, it would not make much difference.

Let’s take a closer look at the red beast ->

Scythe Ninja CU : Closer Look

There’s no mistaken what material is used for the Scythe Ninja CU, all photos have a nice red glow to it, the Ninja CU is a copy of the Ninja Rev B, but with copper fins instead of aluminum fins.

The build quality is excellent and we couldn’t find any faults:



The heatpipes are spread out evenly at each side of the Ninja CU:




The base is flat and polished almost to perfection:



Installation

You can install up to four 120mm fans if you have enough fan clips, the metal clips are held in place by sliding them in the cutouts of the copper fins:



The low speed fan included is a Scythe model SY1225SL12L , this fan has more blades than the average 120mm model, but they are thinner:



Installation of the heatsink on the motherboard requires you to first install the correct bracket on the heatsink:



For S775 you install a custom bracket on the motherboard and use the included back plate for extra strength supporting the weight of the Ninja Copper. Installation requires motherboard removal and takes a good 5~10 minutes, taking care of mounting the brackets on the motherboard, when that’s done it’s a matter of clipping the Ninja in place.

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For our passive CPU cooler tests we included results where we placed two cardboard cutouts at the top and bottom of the heatsink, creating a duct, this mods takes 2 minutes to implement and has proven successful in the past.



Onto our next candidate ->

Coolermaster Hyper Z600

Coolermaster is the big daddy when it comes to PC component cooling, they are partners with NVIDIA for designing their reference VGA coolers and they have OEM partners by the dozen who use Coolermaster products in plenty of retail products.

With this steady revenue stream they allow themselves to be a bit more eccentric in the enthusiast market; in the introduction we mentioned that Thermalright gained quite a bit of popularity with their SP-94 Intel heatsink… well Coolermaster had their own killer product back in 2004… wonder if this description sounds familiar, quote from our review of the Hyper6:

The king is dead, long live the king! It took 6 heat pipes and 1kg of copper but Cooler Master pulled it off and brought us an SP-94 killer. The sheer size is daunting and this heatsink is targeted directly at the enthusiasts who are looking for the best of the best.

The first in the Hyper series, was the Hyper6, it was one of the first Tower CPU coolers and as you can see it meant business. Fast forward 4 years later and they are back with the Hyper Z600, a beast of a cooler which is much larger in dimension that the original Hyper6 and also weighs slightly over 1000gram. Does it have what it takes? Let’s start at the beginning: packaging:



Simplicity is king, a very clean design of the retail box, a very large logo of Coolermaster at the front which shows you to a topview of the cooler inside… but wait that logo is really shiny and bumpy, could it be…



Talk about fancy packaging, the logo at the front is actually pasted onto the cardboard box to really show you “bump-mapping”.

Specifications



No fan specs available as the Hyper Z600 ships without fan included, designed for low noise it can be used fanless and Coolermaster wants you to know it. The cooler is taller and bigger than the Scythe Ninja CU in dimension, but uses a combination of aluminum fins and copper heatpipes/base to reduce weight.

In the Box



Inside the box you’ll find everything needed to get this heatsink installed, and then some:

One big Hyper Z600 Heatsink

Installation manual in 18 languages!

Mounting material for AMD/Intel platforms

A tube of thermal paste

2 pair of plastic fan mounting clips

This package is complete, a thermal paste tube which can be reused when you reinstall the cooler later on, the fan mounting clips are simply genius, the work very well and easy, but more on that later.

Let’s take a closer look at the new Hyper Z600 ->

Coolermaster Hyper Z600 : Closer Look

The Hyper Z600 is build like a four leaf clover, there is no better description; there is a concentration of aluminum fins in those areas where a fan creates the most airflow, the area directly behind the fan motor is empty and if it were filled would not make much of a difference.

By choosing this design path Coolermaster can find the ideal balance between weight, surface area and cooling power:



There are a total of 6 U-form heatpipes joined in a copper ionized base, the plastic top cover is for looks only, doesn’t really serve any purpose, but look nice if you happen to have a case with a window.



The base is machine lapped, very flat and in mint condition when you remove the plastic protective sticker:



Installation

Coolermaster redesigned their CPU Cooler mounting system at the end of 2006 for their enthusiast CPU cooler products (those who weigh a lot). This mounting system requires motherboard removal but offers a very secure fit of the heatsink on the CPU; the mounting system for the Z600 is tweaked slightly with the inclusion of a metal back plate.

Instead of securing the CPU cooler to the motherboard/mounting bracket, you secure the motherboard to the CPU cooler. You install the appropriate mounting bracket to the Z600, you flip it around then place the motherboard on top and screw everything in place with the back plate in place.



It’s an alternative approach to CPU cooler mounting but effectively frees up space around the CPU socket area normally reserved for mounting screws, now you can have more copper/aluminum in that area to help cooling!

The fan mounting clips are excellent, you screw them onto your 120mm fan of choice and then you slide them over the side of the Z600 where you want it, they stay in place from the get go and are easy to remove as well;



Once everything is installed the Hyper Z600 takes up quite a bit of space inside a mid-tower Antec case:



But as long as we can still close the side panel there is no problem, the Z600 is tall, but not too tall:

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For our passive cooling tests we also installed our high-end cardboard pieces to create an air duct:




With both contestants introduced it’s time for some action ->

Test Setup and Competition

We build a S775 system with parts from Alternate.de, the CPU is one hot running Pentium 4 524, 3.06Ghz. It is mounted on a Swiss-army knife equivalent of motherboards: an Asrock 775Dual-VSTA.



The mounting system on S775 is quite straight forward and well thought out, 4 holes around the socket serve as mounting points for the push pins on the standard Intel cooler. Installation is a snap, and removal is very easy too.



With the stock cooling and at stock voltage the 3Ghz P4 was running stable at 3.68Ghz, quite a nice improvement from default speeds.

A Watt Meter recorded peak power consumption under heavy CPU load at 138W, which is less than our previous Athlon 64 setup which consumed up to 165W. The Asrock bios lacks CPU voltage manipulation, so at default voltage is seems this Prescott setup is more power friendly then the over-volted AMD system.

We’re using a compact Antec Sonata II mid tower case, swapped out the PSU for a passive model from FSP rated at 400W, the outside of the PSU case never went past 40°C during our stress tests,

Intel S775 Setup
CPU	Pentium 4 524 @ 3628Mhz - 1.36v vcore
Mainboard	Asrock 775Dual-VSTA
Memory	1 * 512Mb Mushkin PC3200 LVLII V2
Other	Antec Sonata II with AcoustiFan DustPROOF 120mm @ 5v in the rear as outtake (mounted with soft-mounts) ATI R9000 Passive Cooling FSP ZEN 400W Passive Cooled PSU Seagate 7200.8 200Gb HDD in Scythe Quiet Drive

in-take temperature was measured at 22°C for all tests, but temp fluctuations, different mounting and user error can account up to 1-3°C of inaccuracy in the obtained results. Please keep this in mind when looking at the results. Each heatsink was tested repeatedly; if we got questionable results the test was restarted.


example: dBA meter is placed right at the edge of the case - with side panel removed

Noise level of each HSF combo was recorded with SmartSensor SL4001A, the sensor was placed ~5cm away from the side of the case with panel removed. The lowest dBA reading in the test room was 36dBA! with system running without HSF fan.

System was stressed by running K7 CPU Burn for 30min (after Thermal Compound's burn-in); this application pushes the temperature higher than any other application or game we've yet encountered. Speedfan was used to log maximum obtained temperatures.

Arctic Silver kindly send us their “Lumière” thermal testing compound which has the same colour as Ceramique, but only a break in time of 30min!

Arctic Silver's ArctiClean was used to clean off thermal paste of the CPU and heatsink between tests

Fans used for comparison

Delta FFB1212VHE 120x38mm Very High Speed provided by Sidewinder Computers

151CFM – 3200RPM – 12V fan

To eliminate as much variables in the tests we test each heatsink with a "reference" fan if it can be mounted.

GlobalWin NCB 120x120x25mm fan with 41.7CFM rating.

Delta NFB0912L 92x92x25mm fan with 42CFM rating.

Delta FFB1212VHE 120x120x38mm with 151CFM rating.

The Competition

These are the heatsinks we have tested so far on this platform and will compare with:

Arctic Cooling Freezer 7 Pro

Auras CTC-868

Auras GTO-990

Auras LPT-709

Coolermaster Vortex 752

Coolermaster Sphere

Coolermaster Hyper 212

Coolink Silentator

Coolermaster Eclipse

Coolermaster Hyper TX

Coolermaster GeminII

Coolermaster Mars

Evercool Buffalo

Noctua NH-U12

Noctua NH-U12P

OCZ Vendetta

Rosewill RCX-Z5-Ultra

Rosewill RCX-Z775-EX

Scythe ANDY Samurai Master

Scythe Kama Cross

Scythe Katana 2

Scythe Ninja

Thermalright IFX-14

Thermalright SI-128

Thermalright Ultra-120 A

Thermalright Ultra-120 Extreme

Titan Amanda TEC

TTIC BIG

TTIC NPH-1000

Tuniq Tower 120

Ultra ChillTec Thermo Electric CPU Cooler

Xigmatek HDT-S1283

Xigmatek HDT-S1283 “Red Scorpion”

ZEROTherm BTF90

Zalman CNPS9700LED

Zalman CNPS8700

and four Intel stock heatsinks:

Intel Reference Alu (included with older Pentium 4 S775 and Intel E2xxx)

Intel Reference Alu/Cu (included with Core 2 Duo models)

Intel Reference Alu/Cu Big (included with Core 2 Quad models)

Intel Reference Extreme (included with Core 2 Quad Extreme Models)

Onto the results ->

Performance Results

Here we compare the performance of the Scythe Ninja CU and Coolermaster Z600 with different fans, fan speeds and display the data in a chart showing both maximum CPU temperatures obtained under load, as well as noise levels at those settings.

We sorted the obtained data by Noise level ranges, then by lowest CPU temp. Since we measure our dBA level from very close distance, the numbers by themselves have little value without some information. Ambient noise in the room was 36dBA, so we used the following “categories”:

Extremely Noisy: >57dBA. These heatsinks can be heard from the room next door, if you are into overclocking the results obtained here will be most interesting if you don’t care about becoming deaf.

Moderately Noisy to “Not so bothersome”: All results between >44-56< dBA, while the difference between the two extremes is “twice as loud” the loudest reading at 56dBA will be do-able for most, while those who want it quieter should look at the results below 50dBA.

Quiet to Whispher Quiet: Any result under 44dBA is included here, you’ll have to focus to hear the fan running with these CPU coolers, on most you’ll be unable to do that unless you take the PC in very very quiet room and open the side panel and have no other actively cooled component inside the PC.

In the chart below we have added a few descriptions after each heatsink’s name to tell you how we tested them.

We hooked the fan up to a Zalman Fanmate2 which gives 11V at “@ High” and 5V at “@ Low”.

Some heatsinks did not allow manual fan speed regulation, those are marked with “@ Auto”

While testing some of the heatsinks with their fan "@ Low" the system overheated, instead of reporting no data, we decided to measure the fan noise and stop fiddling with the fan controller when the dBA meter read 45dBA. These results are marked “@ Low(er)” in the chart.

“+Stock” means tested with the fan included with the heatsink, “+Papst” or “+NCB” or “+Delta” or “+Delta 3200rpm” means respectively that the heatsink is tested with a 120mm Papst fan, 120mm NCB Globalwin fan, Delta 92mm or Delta 120mm High Speed fan.

In the charts below you can find the results of the new heatsinks colored yellow. Those tests done without a fan installed on the heatsink are marked in blue, we also have 2 results where we used the cardboard - duct tagged appropriately.



Results analyzed and conclusive thoughts on the next page ->

DATA Analysis

Let’s start with the Ninja Copper which performed exactly as Scythe said it would, equipped with the reference fan it performed 1~2°C better than the original Ninja. Seeing as the price of the CU version is almost double, it’s very hard to recommend it. Looking at the product as a whole, equipped with the stock 800rpm fan it delivers impressive performance numbers, noise wise the stock fan is dead quiet at 12v and comes in third in the low noise ranking, only ~2 degrees hotter than the Thermalright IFX-14. Undervolting the stock fan can be done and the noise dropped even further, 1dBA over ambient @ 1cm is stellar, the CPU temperature remains very acceptable at 56.5°C.

The Coolermaster Hyper Z600 was able to best the original Scythe Ninja by a 1~2°C degrees, swapping places with the Ninja Copper in the result chart; this is not an easy feat and we were quite impressed by this cooler’s performance.

The Passive load tests is where the gloves come off, both coolers are at their operation limit when paired with this Pentium 4 Prescott CPU, you’ll probably get away passively cooling a Core 2 Duo with a mild overclock or a stock running Core 2 Quad, but the benefits of adding a very low speed fan are not to be ignored, as they easily shave of 10°C of the load temperatures. If you meet the requirements for passive cooling (low overclock, low heat output CPU) then you can confidently run the Ninja CU and Hyper Z600 without a fan attached, do take note that a case fan is required, a 120mm mounted in the rear is the ideal setup.

In the compact Antec Sonata 2 case both heatsinks are quite close to the rear exhaust fan which does help in the passive cooling tests. Our first load test has both coolers at ~69°C which is high, but not yet too high. When we installed our cardboard cut the temperatures noticeably dropped, ~5°C for the Z600 and ~7°C on the Ninja CU, at this point the load temps are very acceptable taking into account that we’re running without a fan installed. However we are neglecting one cooler which also completed our passive load tests, the Thermalright IFX-14 is a massive and expensive copper/aluminum heatsink, in our test setup it sat very close to the rear exhaust fan and without custom duct managed to keep the CPU at 56°C, grabbing the performance crown in this test.

Conclusive Thoughts

In this shootout we compared the performance and noise production of two new CPU coolers, the Scythe Ninja Copper and Coolermaster Hyper Z600 produced very similar results on our test bench. What we haven’t yet mentioned is the price of the Hyper Z600, we already know that the Ninja Copper will set you back close to €55, the Coolermaster Z600 uses less expensive material and is available for much less, €40! For comparison the Thermalright IFX-14 costs €60.

The Scythe Ninja CU did not improve much on the original Ninja Rev B which comes at a price of ~€35; this leaves us with the choice between the IFX-14, Hyper Z600 and Ninja AlCu. Price/Performance the IFX-14 falls behind as it costs almost twice as much as the competition; the Hyper Z600 is slightly better than the Scythe Ninja but not by much, it also costs a bit more and doesn’t come with a fan. It does include more extra’s for extra fan mounting and overall mounting system and consistent performance is not something to be ignored.

If you are in the market for a high end CPU cooler at an acceptable price both Scythe Ninja RevB and Coolermaster Hyper Z600 will make excellent choices; the Ninja Copper is too expensive for the slight benefit it offers; if cost is no factor the Thermalright IFX-14 remains first choice, if you can fit it inside your case.

We hope our tests help you make an informed decision, we won’t call one product the winner as the differences in noise/performance are very closely matched, and prices change constantly and depend on the region you live in. We can however recommend the Hyper Z600 and Ninja Rev B Plus for offering and excellent price/performance/noise ratio!




We thank Joost from Coolermaster and Hiro from Scythe for sending in their products for test, until next time!