This article covers Thermalright Peerless Assassin 140 SE CPUエアクーラー 6本のヒートパイプ付き 厚さ28mm パフォーマンスグレードファン 158mm 高CPU冷却 AM5.

Overview

The Thermalright Peerless Assassin 140 SE is a dual-tower dual-fan air CPU cooler that delivers impressive cooling performance at an aggressive price point. With six direct-contact heat pipes and aluminum fins, it keeps height to just 158mm while packing two PWM fans: a 120mm unit (TL-C12C-X28 V2) running up to 1850 RPM and a 140mm unit (TL-D14CB) up to 1500 RPM. Combined airflow reaches about 166.69 CFM, making this cooler a strong contender for mid-range to high-end gaming rigs without breaking the bank.

Compatibility Guide

This cooler supports AMD sockets AM5 and AM4, as well as Intel LGA1851, LGA1700, LGA1200, and LGA115x (1150/1151/1155/1156). The overall height of 158mm fits most mid-tower cases, but always verify your case's CPU cooler clearance before purchasing. For memory clearance, the 140mm fan overhangs the RAM area. Standard-height memory modules usually clear it, but tall RGB memory sticks or those with large heat sinks may require shifting the fan upward or opting for low-profile RAM.

Product Info

The Peerless Assassin 140 SE is marketed by Thermalright as a performance-grade air cooler, typically retailing around ¥8,700 (about $55 USD) on Japan. It has been available since at least 2024–2025. It positions itself as a budget-friendly alternative to flagship air coolers like the Noctua NH-D15, trading some absolute cooling headroom for a much lower price. Warranty length is standard for Thermalright products (often 2–3 years), though confirm with the manufacturer.

Best Use Cases

This cooler is ideal for value-oriented builders. For example, pairing it with a Ryzen 5 7600 or Core i5-14600K provides excellent thermal management with headroom for overclocking. It also suits users who need to cool a Ryzen 9 7900X or Core i7-13700K under heavy workloads without moving to liquid cooling. However, if you are building a compact Mini-ITX system or prioritize flashy RGB aesthetics, a smaller air cooler or AIO might be a better fit.

Things to Consider

The biggest consideration is physical clearance. At 158mm, it might not fit in smaller cases. Also, the dual-tower design can interfere with some motherboard components, especially the top PCIe slot on closely spaced boards. For extreme CPUs like the Core i9-14900K or Ryzen 9 7950X, this cooler will struggle during sustained all-core loads; a high-end 240mm or larger AIO is safer. Additionally, the mounting system uses a backplate that can be tricky to install if your case has limited rear access. ## FAQ
Q: Can this cooler handle a Core i9-14900K? A: It fits the socket, but cooling capacity is borderline for a 253W TDP chip. It may work for gaming, but for rendering or heavy multithreaded loads, temperatures will likely hit 95°C. Consider water cooling for such CPUs. Q: Will it interfere with my RAM? A: The 140mm fan on the front tower overhangs the memory slots. Standard-height RAM (up to ~33mm) is fine. Taller sticks may require moving the fan clip slightly higher or using low-profile RAM. Q: How difficult is the installation? A: It uses a universal backplate (SS2) that works with all recent sockets. The process is straightforward but requires care aligning the backplate and tightening screws evenly. The manual is picture-based and adequate.