Weighing in at 1190 g with fans, Scythe's Ninja 5 is an exceptionally large cooler offering middle of the pack performance. It also hangs over all four DIMM slots with the fans installed. However, more is going on behind the scenes than you might expect. While performance isn't top tier, that is due to the two Scythe Kaze Flex fans maxing out at 800 RPM. This results in the Ninja 5 tying for the lowest noise output of any cooler I have tested. Thus, a trade-off of maximum performance was made with that in mind. Obviously, changing out the fans to something faster will result in better performance, but that would negate the Ninja 5's best aspect, which is the fact that it is literally silent at all times.

If you want a high-end air cooler with better performance and low noise, your only options are the Be Quiet Dark Rock Pro 4 or Noctua NH-D15/NH-D15S. All of those options cost far more, and while performance is better, they end up being 2–5 dBA louder when pushed to their limit. Simply put, the Ninja 5 is better than one might expect since it offers a compelling mix of low noise output, performance, and price.

It probably doesn't hurt that build quality is solid, and the mounting hardware is quite easy to work with as well. Thus, potential buyers can rest assured they are getting a great product overall. It is also good to see that rather than giving an older design a simple face-lift, Scythe further improved the Ninja series design by adding cutaway fins for improved memory compatibility. While this addition is not perfect considering the fan will need to be moved up for taller memory modules, it does help improve compatibility.

Memory that is 44 mm or shorter, such as G.Skill's Trident Z kits, for example, will fit without too many issues. Granted, the fan did need to be raised up slightly to clear said DIMMs, but not by enough to impact performance or significantly increase the cooler's height. However, if you have or plan to use memory that is taller than 44 mm, you will likely encounter some conflicts in one way or another, and buyers will want to keep that in mind. There is also the fact that this cooler likely won't be an option for those running RGB-equipped memory, at least when installed in the traditional way.

Overall, with cooling performance that keeps our test system's Intel i7-8700K running smoothly at 4.8 GHz while staying below 40 dBA, there are very few products available that rival what Scythe brings to the table with the Ninja 5. The only other cooler I have tested with similar noise levels is the Thermalright True Spirit 140 Direct, which, while competitive at lower load levels, falls behind when the CPU is placed under extreme workloads. While these loads are not indicative of real-world usage, it does show that the Ninja 5 has far more headroom, which is good for those in warmer climates or with hot and power hungry processors.

If you are looking for a solid performer that is silent with enough headroom for proper overclocking, the Scythe Ninja 5 is certainly one of the few options available at an affordable price.