Noctua NH-L9x65 chromax.Black vs Thermalright Assassin X 120R Digital ARGB Black
Updated August 2026 — Noctua NH-L9x65 chromax.Black wins on cooling eff. and noise level, Thermalright Assassin X 120R Digital ARGB Black wins on value.
The Noctua NH-L9x65 chromax.Black excels in compact builds with silent operation, while the Thermalright Assassin X 120R offers strong performance at a budget-friendly price.
Why Noctua NH-L9x65 chromax.Black is better
Performance
Better suited for low to moderate heat CPUs.
Noise
Operates quieter due to Low-Noise Adaptor.
Design
Compact size fits in tight spaces without interference.
Why Thermalright Assassin X 120R Digital ARGB Black is better
Price
Significantly cheaper at $24.90.
Aesthetics
Digital screen and ARGB lighting enhance visual appeal.
Heat Dissipation
Higher fan speed and airflow for robust cooling.
Overall score
Specifications
| Spec | Noctua NH-L9x65 chromax.Black | Thermalright Assassin X 120R Digital ARGB Black |
|---|---|---|
| Fan Speed | N/A | 2000 RPM |
| Noise Level | ≤ 23.6 dB(A) | ≤ 29.8 dB(A) |
| Compatibility | Intel/AMD | Intel/AMD |
| Thermal Paste | NT-H1 | N/A |
| PWM Support | Yes | Yes |
Dimension comparison
Overview of the Noctua NH-L9x65 chromax.Black
The Noctua NH-L9x65 chromax.Black is a premium low-profile CPU cooler designed for compact builds. It features a total height of only 65mm, making it an excellent choice for small form-factor (SFF) setups and HTPCs. This cooler is particularly well-regarded for its efficient cooling capabilities while maintaining a quiet operation.
Equipped with a highly optimized NF-A9x14 slim 92mm fan, the Noctua operates with PWM support and includes a Low-Noise Adaptor. This ensures automatic speed control for ultra-quiet performance, even under load. Noctua backs this product with high-end NT-H1 thermal paste and an easy-to-use SecuFirm2 mounting system, compatible with a wide range of Intel and AMD sockets.
Overview of the Thermalright Assassin X 120R Digital ARGB Black
The Thermalright Assassin X 120R Digital ARGB Black presents itself as a robust option with an attractive digital screen top cover. This cooler stands at 151mm tall, which allows for significant heat dissipation thanks to its four heat pipes and a powerful 2000RPM fan. It is designed for users who seek both performance and aesthetics in their cooling solutions.
This product features a digital display that provides real-time information about CPU and GPU temperatures along with usage statistics, making it a unique offering in the market. The ARGB fan synchronization allows for customizable lighting, which can be a significant draw for gamers and PC enthusiasts. With wide compatibility across both Intel and AMD platforms, the Assassin X 120R is versatile enough to fit various builds.
Price Comparison
When it comes to pricing, the Noctua NH-L9x65 chromax.Black is priced at $79.95, while the Thermalright Assassin X 120R Digital ARGB Black is significantly cheaper at $24.90. This makes the Thermalright about 69% less expensive than the Noctua. For budget-conscious consumers or those building a system without high thermal demands, the Thermalright offers an attractive price point with features that justify its cost.
However, the Noctua's price reflects its premium build quality and performance, especially in compact configurations where space is at a premium. Each cooler targets different market segments, making the price comparison particularly relevant for specific use cases.
Performance Considerations
In terms of performance, the Noctua NH-L9x65 chromax.Black is recommended for CPUs with low to moderate heat dissipation, such as Intel’s 285K series and AMD’s Ryzen 7000 series. This makes it ideal for silent operations in compact environments. The optimized fan design ensures that it can maintain low temperatures without generating excessive noise.
Conversely, the Thermalright Assassin X 120R Digital ARGB Black is built for more robust cooling demands. With a fan speed of up to 2000RPM and an air volume of 70.84 CFM, it excels in dissipating heat, making it suitable for more powerful CPUs. The combination of its higher height and advanced design allows it to handle significant thermal loads, which is essential for gaming or heavy computational tasks.
Aesthetic Appeal
Aesthetics play a crucial role in modern PC builds, and here both coolers approach this aspect differently. The Noctua NH-L9x65 chromax.Black presents a sleek and understated design, particularly appealing for users who prefer a minimalist look in their builds.
On the other hand, the Thermalright Assassin X 120R features a digital screen and ARGB lighting, which enhances its visual appeal and provides a contemporary look. This cooler can be integrated into gaming rigs where visual flair is as important as performance. The contrast in design philosophy means that consumers can choose based on their aesthetic preferences.
Installation and Compatibility
Installation convenience is a highlight for both coolers, but they cater to different needs. The Noctua NH-L9x65 chromax.Black includes a SecuFirm2 mounting system that simplifies the installation process across multiple Intel and AMD sockets. Its low profile also means it won't interfere with RAM or PCIe slots, making it a hassle-free choice for compact builds.
In contrast, the Thermalright Assassin X 120R also boasts wide compatibility, supporting Intel’s LGA 1851, 1700, and several AMD sockets. However, due to its larger size, it may require more consideration regarding case compatibility. The installation process is straightforward, especially with the provided accessories, although it may need the motherboard's backplate for AMD installations.
Noise Levels
Noise levels are an essential aspect of CPU coolers, especially for users focused on building a quiet PC. The Noctua NH-L9x65 chromax.Black is designed for ultra-quiet operation, thanks to its Low-Noise Adaptor. This allows it to operate quietly, making it ideal for environments where noise is a concern.
The Thermalright Assassin X 120R, while also designed to operate quietly, has a maximum noise level of 29.8 dB(A) due to its higher RPM fan. This level is still reasonable for most users, but it may not be as quiet as the Noctua, especially under load. For users prioritizing silent operation, the Noctua may have the edge.
Which should you buy?
Choosing between the Noctua NH-L9x65 chromax.Black and the Thermalright Assassin X 120R Digital ARGB Black ultimately depends on your specific needs. If you are building a compact, silent PC and are willing to invest in quality, the Noctua cooler is the superior choice with its award-winning design. However, for those looking for a more budget-friendly option with strong performance and aesthetic appeal, the Thermalright cooler presents a compelling alternative. Each cooler has its strengths, making the decision largely influenced by your build requirements and personal preferences.

