Scythe Ninja 5: evolution of the revolutionary predecessor

Test procedures

The fourth Ninja was a pleasant surprise (mainly because of its unattractive predecessor). Scythe used improved version of the first two designs, and shortly after created popular Fuma series based on Ninja 4. Fuma rev. A was the best deal for the money, although the current second version is a bit different story. Now there’s the new Ninja 5 that looks very promising. The core remains unchanged, but the cooler is bigger and stronger than before.

Basic parameters

*These measures indicate distances between the cooler and RAM slots, or more precisely the nearest PCIe × 16 slot.
**The data reflect the situation on Mini-ITX boards which typically have 50 mm from the center of the socket to the first slot. With the ATX format, it can be up to 7 mm more and that means one extra slot and a wider compatibility than is mentioned in the table. We measured the height limit with fans that are aligned with the maximum specified coolers height.

Details

Before we get to the point, we’d like to mention that the protection of the components in the package has improved. This was one of the usual drawbacks of Scythe coolers, but this time, the heatsink is safely fixed in a foam.

The transformation of the heatsink is minimalistic, the least significant in the series. The basic features are the same as before, and the difference in the shape of the ribs is barely noticeable, they are slightly extended on the sides. Dimensions in both axis remained virtually unchanged. Only the depth is 5 mm bigger, which is probably because of the overhang of the clamping brackets for fans. Either way, the height of the heatsink is the same and the weight increased to 145 grams.

The original number of ribs (36, Ninja 4) was increased by another five (Ninja 5), and they have the same thickness (0.4 mm). Just the gaps between them got narrower, from 2.6 to 2.2 mm. The construction is solidly massive, only the top rib doesn’t feel very firm.

The direction and distribution of heatpipes is identical to the design of its older brother. The base itself is convex in both directions, but significantly more in the direction of the heatpipes, it is barely visible in the opposite direction.

The surface of the base is glossy, almost as a mirror, and there is a soft circular scoring. It is so soft that you cannot even feel it, just see it. However, it is enough for compounds with higher viscosity. By the way, according to tests, the supplied one is pretty decent.

There are some radical changes when it comes to fans. Only the format is the same – 120 mm. The first change is that there are two fans in the package, not just one. The intention is obvious, to make cooling of the rear area of ribs more effective even at low RPM. Overall, the max. fan speed is quite low (maximum at 12V is 834 rpm) and the min. limit is extremely low, the rotor is still active even at 2.52V (60 rpm), although this setting is not very “healthy” for the fans and they make an odd noise that doesn’t go away until 3.45 V (~ 200 rpm). From this point, the only source of sound is the aerodynamic noise. Casual operation of SU1225FD12L-CDP (the full name of the model) doesn‘t produce any undesirable, parasitic sounds.

The bearings have also been improved – the typical slide type (Ninja 4) was replaced by the fluid type (FDB). Even though they don’t have the robustness of the high-end Scythe Grand Flex. The original Ninja 5 fans weigh 130 g (per piece), so they are rather lighter than heavier, and the blades have an average thickness.

There are eleven blades in total, so two more than before, but it seems that the area of one blade is the same. There is no milling (that helped to direct the airflow) on the surface this time, and the manufacturer has also simplified the design by removing the manual voltage control switch which could be used to limit PWM. One thing that was added is rubber pads in the corners.

As a part of the installation kit, you also get a long-tip screwdriver that is necessary for the installation of the heatsink. The mounting system is otherwise classic – extended backplate with long screws, a pair of brackets, and a cross clamp which in this case is already pre-installed on the cooler‘s base.

Thanks to its construction, Ninja 5, as one of few coolers (and probably the only one with a weight over one kilogram), makes it possible to install the cooler on the socket with mounted fans. The assembly process is simple and comfortable. Of course, you need to keep in mind that it is a large cooler and the installation can be a bit tricky in smaller cases.

With the fifth Ninja, Scythe has also tried to improve compatibility with RAM modules. You can put modules with a height of up to 6 cm to the first two slots, but only if you don’t use fans. With fans, the second slot is limited to 4 cm (although it’s not that terrible, majority of modules can fit in, including the top G.Skill Flare X). You can also put your fans higher, but to maintain 6cm compatibility this way, the overall height of the cooler will increase to 175 mm, which might be too much for a lower chassis.

You don‘t need to worry about a conflict with your graphics card, even motherboards with the first Express × 16 slot closer to the processor are fine. An exception could be some older Mini-ITX boards. It’s 69 mm from the center of the socket to the PCB/backplate of the graphics card.

It‘s a shame that Scythe has abolished exclusive fan installation on all four sides, which made Ninja coolers exceptional. Now you can choose from two sides only. Especially AMD owners will not be happy about this since they can usually orient the heatsink only in one direction, so it’s impossible to direct the airflow to the ceiling.

The fourth Ninja was a pleasant surprise (mainly because of its unattractive predecessor). Scythe used improved version of the first two designs, and shortly after created popular Fuma series based on Ninja 4. Fuma rev. A was the best deal for the money, although the current second version is a bit different story. Now there’s the new Ninja 5 that looks very promising. The core remains unchanged, but the cooler is bigger and stronger than before.

Test procedures

Tests begin with the analysis of fans. Using the Gophert CPS-3205 II laboratory power supply and the UNI-T UT372 laser tachometer, we detected the initial speed. That means determining the minimum voltage required to move the rotor in the idle stage. Subsequently, we regulated the revolutions by hundreds (from 400 rpm to the round maximum), which gave us the first part of the data to create a curve that indicates the noise increase according to rpm. To make the results as accurate as possible we took the average values of 30 seconds long sequences and regulated the fans by the hundredths of volt until the tachometer reached a specific value, for example 800 rpm. Finally, we noted down the maximum rpm and put values into the parameters table.

To assign a specific noise level to a specific speed, we put the coolers with corresponding voltages to the soundproof box in which we measured the noise. This was done using the Reed R8080 sound level meter that was recalibrated before each set of measurements. The positions of the polyethylene pad on which the coolers were fixed, and the sound level meter were always the same. To achieve the most precise logging even with the lowest flow the distance between the sensor of the meter and the fan was approximately 25 cm. Each measurement was performed in real time. The meter sent 30 sound samples to the computer, from which we took the average value and put it into the charts. The most important part was to find and to align the fan settings to fixed noise levels. In this case, 45, 42, 39, 36, 33, and 31 dBA were selected, and with the exception of the last and the penultimate mode, each further decrease of rpm reduced the noise level by a half. On the one side there was noisy 45 dBA and on the other almost completely silent 31 dBA.

If one of the modes is missing in the charts, it is either due to insufficient cooling performance or because it was not possible to regulate the fan to the desired noise level. Each test lasted 600 seconds. We simulated the burn in IntelBurnTest (7500 MB) and the result represents the average of maximum temperatures of CPU cores, which were captured in Core Temp. At the time when some of the cores reached 95 °C, the tests were interrupted and considered unsuccessful.

Cooling performance tests were done in our plexiglass wind tunnel with a motherboard in the vertical position, just like in a usual tower case. The scheme of the system cooling was traditional, balanced flow was provided by four Noctua NF-A12S PWM fans. Two were at the input and two at the output, regulated to 550 rpm.

The intake air temperature was 21 – 21.3 °C, ensured in our air-conditioned lab so we could also accurately measure the automatic regulation PWM. Only during this process we put the processor with TDP 140 W back to the factory settings. The curve of the profile of the impulse modulation was set, regarding to low noise level, to 20 % ≤ 20 °C – 30 % ≤ 40 °C – 40 % ≤ 60 °C – 100 % ≤ 90 °C.

*Without overclocking, the power consumption of the configuration during IntelBurnTest load was around 170 W; 225 W with overclocking (approximately 180 watts by processor).

The fourth Ninja was a pleasant surprise (mainly because of its unattractive predecessor). Scythe used improved version of the first two designs, and shortly after created popular Fuma series based on Ninja 4. Fuma rev. A was the best deal for the money, although the current second version is a bit different story. Now there’s the new Ninja 5 that looks very promising. The core remains unchanged, but the cooler is bigger and stronger than before.

Automatic regulation

The fourth Ninja was a pleasant surprise (mainly because of its unattractive predecessor). Scythe used improved version of the first two designs, and shortly after created popular Fuma series based on Ninja 4. Fuma rev. A was the best deal for the money, although the current second version is a bit different story. Now there’s the new Ninja 5 that looks very promising. The core remains unchanged, but the cooler is bigger and stronger than before.

Max. RPM

The fourth Ninja was a pleasant surprise (mainly because of its unattractive predecessor). Scythe used improved version of the first two designs, and shortly after created popular Fuma series based on Ninja 4. Fuma rev. A was the best deal for the money, although the current second version is a bit different story. Now there’s the new Ninja 5 that looks very promising. The core remains unchanged, but the cooler is bigger and stronger than before.

45 and 42 dBA

The fourth Ninja was a pleasant surprise (mainly because of its unattractive predecessor). Scythe used improved version of the first two designs, and shortly after created popular Fuma series based on Ninja 4. Fuma rev. A was the best deal for the money, although the current second version is a bit different story. Now there’s the new Ninja 5 that looks very promising. The core remains unchanged, but the cooler is bigger and stronger than before.

39 and 36 dBA

The fourth Ninja was a pleasant surprise (mainly because of its unattractive predecessor). Scythe used improved version of the first two designs, and shortly after created popular Fuma series based on Ninja 4. Fuma rev. A was the best deal for the money, although the current second version is a bit different story. Now there’s the new Ninja 5 that looks very promising. The core remains unchanged, but the cooler is bigger and stronger than before.

33 and 31 dBA

The fourth Ninja was a pleasant surprise (mainly because of its unattractive predecessor). Scythe used improved version of the first two designs, and shortly after created popular Fuma series based on Ninja 4. Fuma rev. A was the best deal for the money, although the current second version is a bit different story. Now there’s the new Ninja 5 that looks very promising. The core remains unchanged, but the cooler is bigger and stronger than before.

Conclusion

There are two very important things: revolutions per minute and the price. The more intense airflow, the less attractive this cooler becomes. The best setting for Ninja 5 would be 600 rpm and less. Scythe knows well why they sell this cooler with low-speed fans. With proper settings it‘s better than SPC Fera 3 v2, and a bit less efficient than Noctua NH-D15, but also accordingly cheaper. It all depends on the deal you can get.

The price range is quite wide, 70 € is too much (Reeven Okeanos and Raijintek Nemesis would be a better choice for the money), but if you get a chance to buy it for less than 60 €, go for it. The efficiency/weight ratio is nothing extraordinary, but we decided to give it award “Go for it!“ for the results in low RPM modes and high-quality fans that are not very common in this price category.

This is not the end of Ninja 5 tests on HWCooling. We are working on a passive mode and in-depth testing with reference fans.

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• Contents
• Parameters and details
• Test procedures
• Automatic regulation
• Max. RPM
• 45 and 42 dBA
• 39 and 36 dBA
• 33 and 31 dBA
• Conclusion