by Sergey Lepilov
01/12/2007 | 11:28 AM
More super-coolers are coming out. The recently released Zalman CNPS9700 LED and Scythe Infinity are followed by an all-copper stylish-looking super-efficient CPU cooler from ASUS.
<%BANNER[article]%>This creation of the engineering and designing thought is called Silent Knight. The cooler’s knightly character shows up in its elements as well as packaging.
Here it is:
The cooler comes in a small cute-looking box painted dark and silvery colors:
This cardboard box has a plastic carry handle at the top. The cooler’s main features are described on the face side of the box; a detailed specification is printed on the reverse side. The side panels aren’t empty, either, telling you about the know-how implemented in the cooler’s design.
The knighthood theme is represented on the package and on the cooler with a large-hilted medieval sword. It looks very imposing and stylish.
The box is divided into two compartments:
The cooler lies in a plastic casing in the top compartment. The bottom compartment is occupied by a small cardboard container with accessories. Here they are, each item in a separate pack:
I was at first surprised at finding no speed controller among the accessories, but the cooler is not expected to support one. That’s enough about the box and accessories, it’s time to take a look at the Silent Knight itself.
The new cooler from ASUS resembles Zalman’s CNPS9500/9700 LED, but I think it’s designed better as concerns achieving maximum efficiency.
There are six separate heat pipes instead of the Zalman coolers’ “three like six”. Each of them goes out of the copper plate in the cooler’s base and makes up a loop, ending on the other side of the cooler. The six heat pipes are divided into two groups, three pipes in each. Each group carries 64 copper ribs for a total of 128 ribs. For comparison, the Zalman CNPS9700 LED has 125 such ribs, but the cooler’s dissipation area seems larger overall (ASUS doesn’t tell us the area of the heatsink of the new cooler). On the other hand, the Silent Knight’s fan is located not at the side of the heatsink, but in the center, in between the pipes and plates. This helps make a better use of the air stream because the plates are cooled not only with the blown-out air but also with the air that is being taken from the outside.
The fan is topped with a black aluminum plate. Besides a picture of a sword, the direction of airflow is indicated on the plate’s sides. There is also a slit in its top – I guess it is intended to supply more fresh air.
This plate and the fan are fastened on an aluminum base that is secured with clamps on two heat pipes:
So if the fan fails for some reason, you can try to find a replacement. By the way, the Silent Knight is equipped with a 92mm fan on a sliding bearing with translucent blades and blue highlighting. The fan speed is constant at ~2200rpm, creating 52.25CFM airflow. The amount of noise is not specified. Subjectively, the cooler isn’t loud, but not quiet, either. If you set the 110mm fan of the Zalman CNPS9700 LED at 1950-2000rpm, it will be about as noisy as the Silent Knight.
The diameter of the fan is smaller than the diameter of the heatsink – you can see this even in the photo. I measured the distance from the top of the fan blade to the top edge of a heatsink’s rib and found it to be as big as 15mm! I wonder why they didn’t install a 110mm fan back at the factory and added a speed controller into the bargain. This simple and insignificant improvement would have helped increase the cooler’s efficiency to some extent. Perhaps we are going to meet a Silent Knight Pro in near future?
I also have one idea that can only be implemented at the factory. Why not to place the heat pipes in loops of a different diameter and length instead of same-size loops as they are. The first loop and the two innermost pipes on both sides of the fan would have the biggest diameter. Next there would go smaller pipes, and the outermost pipes would be the smallest. This would ensure a more uniform distribution of heat in the heatsink’s ribs and the fan would have more work to do because the heat pipes, shifted relative to each other, would provide a stronger resistance than if they are placed in a linear manner. That’s why a larger fan is necessary, desirably with adjustable speed so that we could check out the cooler’s performance depending on the airflow strength. That’s only my theory, but I guess it would be interesting to see how it works in practice.
But let’s get back to the Silent Knight. The ends of the pipes are sealed at the cooler’s bottom. The pipes have contact with the base by means of soldering (very neatly done, without a trace of solder on the edges).
The copper plate at the cooler’s base is 3.5mm thick in its thinnest spot, i.e. under the pipes. There is a groove for each pipe – I had complained about the lack of such grooves in my review of the Scythe Infinity.
The cooler’s base left a perfect trace of thermal grease on a piece of glass. Its finish quality is almost ideal, too:
There’s no mirror shine here, but the surface is perfectly flat.
The only thing I have to add in this section is that the weight of the cooler is 610g.
Mounting the Silent Knight on mainboards is a simple and intuitive process. The small manual enclosed with the cooler covers this procedure (for every supported CPU socket) on only two small pages. The cooler supports six sockets in total: Socket 478 and LGA775, Socket 754, 939, 940 and Socket AM2. For each platform there is a universal back-plate with screwed-in bushings.
Socket 478 and LGA775
Socket 754/939/940 and Socket AM2
When installed on an LGA775 mainboard, the back-plate looks like follows:
And if there are elements on the mainboard’s reverse side that prevent you from installing this universal back-plate, you will also find an ordinary compact X-shaped back-plate enclosed with the Silent Knight (you can see it in the photograph of the cooler’s accessories).
So, you’ve picked up the right back-plate for your mainboard, what’s next? It’s simple, but you have to take your mainboard out of the system case. You should use the included long screws and plastic bushings to fasten the steel mounting frame to the back-plate through the mainboard’s PCB:
This universal frame is to be used with every platform supported by the cooler. You could have seen it before in our review of the ASUS Silent Square cooler. The frame stands rather high above the mainboard, so capacitors or any other elements around the CPU socket won’t get in the way.
Don’t forget to put some thermal grease on the CPU before you install the frame. You can use the included grease from ASUS – it is very thick and hard to apply, but is as efficient as Arctic Silver 5. That’s another good point about the new cooler.
After that, you only have to put the cooler down on the frame, insert the pressure clamp between the cooler’s pipes and fix the cooler on the CPU with a latch:
You can position the cooler just as you like on an Intel platform due to the symmetrical positions of the mounting holes in the mainboard. But ASUS has also provided for a proper orientation of the cooler on Socket AM2 and Socket 754/939/940 platforms. You just have to put one more plate (included with the cooler) on top of the steel universal mounting frame:
With this plate, you can choose any orientation for the cooler just as you like. A simple and effective solution.
Winding this section up, I can’t help mentioning the Silent Knight’s blue highlighting which is going to please your eyes at night.
The Silent Knight’s specifications are listed in the following table in comparison with its today’s opponents.
I took a high-performance Scythe Infinity cooler as an opponent to the Silent Knight. This cooler was tested with its native fan at 1200rpm as well as with two 120mm fans working for exhaust and intake at 1200rpm, too. Besides that, I added the results of Zalman’s "copper hedgehogs" CNPS9500 LED and CNPS9700 LED. You’ll see how they compare with each other, by the way.
What’s curious, the three copper coolers are all very similar when looked upon from the fan side:
It’s normal for the Zalman cooler since the newer model is just an enlarged copy of its predecessor. The Zalman CNPS9700 LED and the ASUS Silent Knight are almost the same size when viewed from above:
But the ASUS cooler is turned around by 90 degrees in the photo.
I don’t include the popular super-cooler Thermaltake Big Typhoon because we have tested it a number of times on different platforms and with different opponents, also those that are going to oppose the Silent Knight in this test. So, I see no sense in testing the Big Typhoon anymore.
The coolers are tested on an open testbed as well as in a system case with the following configuration:
There is no AMD platform in today’s tests because it’s pointless nowadays to test coolers on a single-core AMD Athlon 64 due to the decreasing popularity of such CPUs as well as to their lower heat dissipation in comparison with an overclocked Intel Core 2 Duo. And we hadn’t got our AM2 platform ready for this test.
The Chaintech GeForce 7950 GX2 was overclocked from its default frequencies to 580/1580MHz to make the test conditions somewhat harder because the air from the graphics card’s cooler remained in the system case.
The tests were performed in Windows XP Professional Edition Service Pack 2. S&M version 1.8.2b was used to monitor the temperature of the Intel Core 2 Duo E6300 CPU. The CPU was heated up by means of Intel Thermal Analysis Tool for 20 minutes (according to the method we described in the article called Originality or Efficiency? Cooler Master Mars, Eclipse and Hyper TX Cooling Solutions Reviewed). S&M would report a 1.5°C lower temperature than the Intel Thermal Analysis Tool did in Idle mode, but their readings were identical under load.
Considering that Intel Thermal Analysis Tool provides a CPU load untypical of most ordinary applications, I also simulated a Game test mode by running 3DMark06’s Firefly Forest test with 16x anisotropic filtering and without full-screen antialiasing for 19 times. This helps heat up the graphics card and the CPU both together. If FSAA were in use, the GeForce 7950 GX2 would become hotter, but the CPU would bear a smaller load, which is not what I want.
The temperature was read from the sensor integrated into the CPU. The mainboards’ automatic fan speed management was disabled for the time of the tests. The thermal throttling of the Intel Core 2 Duo processor was controlled with RightMark CPU Clock Utility version 2.2 (our processor would begin to skip clock cycles on reaching a temperature of 81.5°C).
I performed at least two cycles of tests in each mode (TAT and Game). I waited for 25-30 minutes for the temperature to stabilize during each test cycle. The maximum temperature in the two test cycles was considered as the final result (if the difference was not bigger than 1°C).
The ambient temperature was monitored by means of an electric thermometer and remained at 24.5-25°C during the tests.
The Intel Core 2 Duo E6300 (stepping B2) was limited in frequency by the weakest cooler in this test (Zalman CNPS9500 LED at 1400rpm), so I overclocked it from its default 1866MHz to 3360MHz (a frequency growth of 80.1%) with a voltage increase to 1.425V.
Two comments about the diagrams. First, the speed of the coolers’ fans is their real (not the specified) speed according to the monitoring tools. And second, Zalman’s coolers were tested at the min and max speed of the fan and I also tested them at some intermediate speed and low noise level when the noise from the fan was not distinguishable against the general noise from a quiet system case.
Here are the results:
So, in the closed system case the ASUS Silent Knight equals the performance of the Scythe Infinity (in its standard configuration) and of the Zalman CNPS9700 LED at 1850rpm. But I should confess the Silent Knight is a little louder than the Zalman and considerably louder than the Scythe Infinity under such conditions. Anyway, the new cooler from ASUS performs well in a closed computer.
On the open testbed it equals the Zalman CNPS9700 LED at 1250rpm and leaves behind the super-cooler of the past, Zalman CNPS9500 LED. It less efficient than the Zalman CNPS9700 and Scythe Infinity under such conditions but the difference of 2°C and 3.5°C, respectively, is insignificant. It’s up to you to decide which test mode (a closed system case or an open testbed) is more relevant for your practical needs.
Comparing the two coolers from Zalman, the newer and larger model wins by 3-5°C in the system case and by 7-8°C on the open testbed! I guess that’s a lot. The CNPS9700 LED also offers a wider speed adjustment range, providing more setup flexibility. I guess this is worth the difference in price with the CNPS9500 LED, which is about $20, but it’s up to you to decide, as always.
The Silent Knight cooler I have tested today has left me with positive impressions and is beyond doubt worthy of the title of super-cooler. Its only drawback is that it is not quiet. The fan is distinctly audible against the general noise from a quiet system case, but the noise level is low. Otherwise, it is a top-notch product without a doubt.
First of all, the Silent Knight proved to be as efficient at cooling our Intel Core 2 Duo processor as the best coolers from Zalman and Scythe. Second, the cooler supports all modern platforms and its reliable and clever fastening mechanism allows you to orient it in the most efficient way on the mainboard. And finally, the cooler has got blue highlighting of the fan, which makes it appealing for modders. You also get good thermal grease with the cooler while its pretty-looking stylish box just asks for you to present it as a gift to an overclocker friend of yours.
As for the price factor, I saw offers asking $89 for a Silent Knight. That’s not much for a super-cooler. But I also hope that an improved version with a 110mm fan, a speed controller and, perhaps, with a slightly changed heatsink design will be released.