Overview
The Thermalright Peerless Assassin 120 SE is a dual-tower air cooler that has earned a reputation as the go-to budget performance pick. It targets builders who want strong cooling for a Ryzen or Intel CPU without paying premium-cooler prices, and it is a natural match for a chip like the Ryzen 7 9800X3D.
This page is a curated summary. CoreForge did not lab-test this cooler. We verify the specifications against Thermalright's official documentation, summarize independent reviewer findings, and add the Canadian pricing and value perspective. The full original reviews are linked in the Sources section.
Verified specifications
According to Thermalright's official product information, the Peerless Assassin 120 SE uses a twin-tower aluminum heatsink with six 6mm copper heat pipes (AGHP anti-gravity design) and a nickel-plated copper base. It ships with two 120mm TL-C12C PWM fans rated up to 1,550 RPM, 66.17 CFM airflow, and a maximum noise level of 25.6 dB(A). The cooler stands 155mm tall, includes thermal paste and mounting hardware, and supports AMD AM4/AM5 and a wide range of Intel LGA sockets.
What the reviews found
According to Tom's Hardware's hands-on testing, the Peerless Assassin 120 SE delivers incredible, affordable air cooling performance, and it has become a reference point for value in the cooler category. The consensus across independent testing and verified user builds is that its performance lands close to much more expensive dual-tower coolers, making it a frequent "best value" pick. In one verified owner report on an AMD 9800X3D build, the cooler kept the CPU in roughly the high-50s to low-70s Celsius range during demanding gaming, reasonable for a chip of that class on air.
Practical notes
Two things reviewers and builders consistently mention. First, the 155mm height is tall, so confirm your case lists enough CPU cooler clearance before buying. Second, some users find the mounting process a bit fiddly, following the included instructions carefully helps. The included thermal paste is fine to start with. On AM5, the cooler reuses AM4-style mounting, and the retention works with the socket's backplate.
The Canadian angle
This is a rare category where Canadian pricing is both low and stable. The Peerless Assassin 120 SE has regularly been available in Canada in roughly the $35-$50 CAD range, often dropping to the mid-$30s on sale, with ARGB and color variants costing only a little more. That makes it one of the easiest value recommendations in a build. Check the current price on Amazon.ca, Newegg.ca, and Canadian retailers, and note the SE, ARGB, and V2/V3 variants differ slightly, buy based on the price and look you prefer.
Bottom line
A verified value champion. For the vast majority of Ryzen and Intel builds that do not need liquid cooling, the Peerless Assassin 120 SE offers near-premium air cooling at a budget price, just confirm case clearance for its 155mm height.


