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For most LGA 1150 computers, the Thermalright Peerless Assassin 120 SE is the strongest overall choice when a 155 mm-tall dual-tower cooler fits the case, memory and motherboard. The Noctua NH-U12S is the safer balanced option for buyers who value easier installation, documentation and long-term support. A verified 120 mm single-tower cooler, such as an exact DeepCool AK400 or Cooler Master Hyper 212 variant, is normally all a locked Core i3, i5 or i7 needs.
Socket support alone does not guarantee a successful installation. Check the case’s CPU-cooler height limit, RAM and VRM clearance, mounting hardware and whether the system is an OEM design before ordering.
Quick recommendations
| Use case | Recommendation | Why |
|---|---|---|
| Best overall value and performance | Thermalright Peerless Assassin 120 SE | Dual 120 mm fans and substantial headroom for roughly 155 mm of case height |
| Best balanced single tower | Noctua NH-U12S | LGA115x support, 158 mm height, strong documentation and a six-year warranty |
| Maximum air-cooling headroom | Noctua NH-D15 | Large dual tower for sustained loads and serious overclocking, if clearance allows |
| Budget replacement | Verified AK400-, Hyper 212- or equivalent single tower | Generally sufficient for a stock, locked Haswell processor |
| Compact case | Exact low-profile or compact model confirmed for LGA1150 | Large tower coolers may exceed the case or block nearby components |
Prices and stock change by seller and country. The Peerless Assassin 120 SE was observed around $33–$36 in United States comparison coverage; treat that as a dated market signal, not a guaranteed price. The budget single-tower class was generally under $50 in the cited comparison coverage. PC Gamer’s review and Tom’s Hardware’s roundup provide that context.
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What LGA 1150 compatibility actually means
LGA 1150 is the socket used by Intel’s Haswell-era desktop Core i3, i5 and i7 processors. Most compatible retail coolers use Intel’s related LGA115x mounting pattern, covering LGA1150, LGA1151, LGA1155 and LGA1156. Noctua’s socket overview shows this grouping, while Intel’s cooler-compatibility guidance explains why the manufacturer’s socket list is authoritative.
#1 Best Overall
- [Brand Overview] Thermalright is a Taiwan brand with more than 20 years of development. It has a certain popularity in the domestic and foreign markets and has a pivotal influence in the player market. We have been focusing on the research and development of computer accessories. R & D product lines include: CPU air-cooled radiator, case fan, thermal silicone pad, thermal silicone grease, CPU fan controller, anti falling off mounting bracket, support mounting bracket and other commodities
- [Product specification]AX120R SE; CPU Cooler dimensions: 125(L)x71(W)x148(H)mm (4.92x2.8x 5.83 inch); Product weight:0.645kg(1.42lb); heat sink material: aluminum, CPU cooler is equipped with metal fasteners of Intel & AMD platform to achieve better installation
- 【PWM Fans】TL-C12C; Standard size PWM fan:120x120x25mm (4.72x4.72x0.98 inches); fan speed (RPM):1550rpm±10%; power port: 4pin; Voltage:12V; Air flow:66.17CFM(MAX); Noise Level≤25.6dB(A), the fan pairs efficient cool with low-noise-level, providing you an environment with both efficient cool and true quietness
- 【AGHP technique】4×6mm heat pipes apply AGHP technique, Solve the Inverse gravity effect caused by vertical / horizontal orientation. Up to 20000 hours of industrial service life, S-FDB bearings ensure long service life of air-cooler radiators. UL class a safety insulation low-grade, industrial strength PBT + PC material to create high-quality products for you. The height is 148mm, Suitable for medium-sized computer case
- 【Compatibility】The CPU cooler Socket supports: Intel:1150/1151/1155/1156/1200/1700/17XX/1851,AMD:AM4 /AM5; For different CPU socket platforms, corresponding mounting plate or fastener parts are provided
An LGA 1151 or LGA 1200 product is therefore often usable, but not automatically. Buy only when the exact model manual or compatibility page says LGA1150/LGA115x, or confirms that the required mounting pattern and hardware are included. Retailer titles can omit older sockets, and product families can contain several revisions.
- Confirm the backplate, standoffs, brackets, screws and spacers are in the package.
- Do not assume a used cooler includes its original LGA1150 hardware.
- Exclude OEM-specific coolers unless the Dell, HP or Lenovo chassis and backplate are explicitly supported.
Noctua’s Compatibility Centre demonstrates the right approach: check the CPU, motherboard, RAM and case together, not just the socket.
Choosing the right cooler
Thermalright Peerless Assassin 120 SE: best overall when it fits
This dual-tower cooler uses two 120 mm fans and is listed for LGA1150 in current retailer coverage. Its approximately 125 × 135 × 155 mm dimensions provide more cooling capacity than most Haswell chips require, which can translate into lower fan speeds during gaming or sustained work. See the PC Gamer review and the Micro Center listing for performance and compatibility details.
- Choose it for: Core i5-4690K or i7-4790K systems, moderate overclocking, long gaming sessions, or future reuse.
- Check first: about 155 mm of case height, front-fan clearance over RAM, VRM heatsinks and access around the first PCIe slot.
- Trade-offs: harder installation and a larger footprint than a single tower; seller revisions and included brackets can differ.
It is not automatically good value if its price approaches that of the entire older PC, or if the case cannot accommodate it.
Rank #2
- Support Intel LGA 1200/1156/1155/1150/1151
- Low Profile Design. Air flow - 31.343 CFM. Noise level - 21.3 decibels
- Optimized for low power CPU's
- 7-Bladed Low Noise Fan
- Quick and Easy Installation
Noctua NH-U12S: the lower-risk balanced choice
The NH-U12S is a single-tower cooler 158 mm tall with a 120 mm NF-F12 PWM fan rated up to 1,500 RPM. Noctua supplies NT-H1 thermal compound, a low-noise adapter and lists a six-year warranty. Its LGA115x support and installation documentation are detailed in the manual and specifications, features page and product overview.
This is a good fit for locked Core i5 and i7 processors, quiet systems and cases where a dual tower would create RAM or installation problems. It is still 158 mm tall, so it is not a low-profile solution, and it often costs more than value-oriented coolers. Noctua’s stated fan figures—up to 22.4 dB(A), or 18.6 dB(A) with the adapter—are manufacturer measurements under its own conditions and should not be ranked directly against unrelated test methods.
Noctua NH-D15: premium air cooling for demanding loads
The NH-D15 is a large dual-tower cooler with LGA115x support. Its product page and datasheet document the dimensions and clearance requirements.
Use it for an unlocked Haswell chip under sustained all-core workloads, a carefully configured overclock, or a system where low fan speeds matter more than cost. It is usually excessive for a locked processor. Tall memory can force the front fan upward, increasing total height, and the cooler may be awkward in a narrow or frequently transported case.
Rank #3
- [Brand Overview] Thermalright is a Taiwan brand with more than 20 years of development. It has a certain popularity in the domestic and foreign markets and has a pivotal influence in the player market. We have been focusing on the research and development of computer accessories. R & D product lines include: CPU air-cooled radiator, case fan, thermal silicone pad, thermal silicone grease, CPU fan controller, anti falling off mounting bracket, support mounting bracket and other commodities
- [Product specification] Thermalright PA120 SE; CPU Cooler dimensions: 125(L)x135(W)x155(H)mm (4.92x5.31x6.1 inch); heat sink material: aluminum, CPU cooler is equipped with metal fasteners of Intel & AMD platform to achieve better installation, double tower cooling is stronger（(Note:Please check your case and motherboard for compatibility with this size cooler.）
- 【2 PWM Fans】TL-C12C; Standard size PWM fan:120x120x25mm (4.72x4.72x0.98 inches); fan speed (RPM):1550rpm±10%; power port: 4pin; Voltage:12V; Air flow:66.17CFM(MAX); Noise Level≤25.6dB(A), leave room for memory-chip(RAM), so that installation of ice cooler cpu is unrestricted
- 【AGHP technique】6×6mm heat pipes apply AGHP technique, Solve the Inverse gravity effect caused by vertical / horizontal orientation, 6 pure copper sintered heat pipes & PWM fan & Pure copper base&Full electroplating reflow welding process, When CPU cooler works, match with pwm fans, aim to extreme CPU cooling performance
- 【Compatibility】The CPU cooler Socket supports: Intel:115X/1200/1700/17XX AMD:AM4;AM5; For different CPU socket platforms, corresponding mounting plate or fastener parts are provided（Note: Toinstall the AMD platform, you need to use the original motherboard's built-in backplanefor installation, which is not included with this product)
Budget single towers: AK400, Hyper 212 and equivalents
A current 120 mm single tower is normally enough for a stock, locked LGA1150 Core i3, i5 or i7. DeepCool’s cooling catalogue contains LGA1150-compatible products, while the Tom’s Hardware roundup places AK400, Pure Rock 2, Arctic Freezer 36 and Hyper 212 families in the value segment.
Those are families, not one universal specification. Confirm LGA1150 hardware on the exact retail model, and verify the included bracket before paying. These coolers give up some thermal and acoustic headroom and may use less robust mounting or noisier fans than premium models, but they avoid spending dual-tower money on an office or general-purpose PC.
Match the cooler to your processor and workload
Locked Core i3 or Core i5
Choose a verified budget single tower. Intel’s stock cooler may function at stock settings, but a modest tower usually improves sustained temperatures and noise, especially in an aging, dusty system.
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An AK400- or Hyper 212-class cooler is adequate; the NH-U12S is the quieter, better-documented upgrade when its 158 mm height fits.
Rank #4
- Cooler Master I30 MINI CPU Cooler 92mm Quiet Fan For Intel 1150 1151 1155 1156 Computer Case CPU Radiator 3pin 9.2cm Cooling Fan,1151 CPU Cooler LGA 1151 For Intel Cooler,LGA 1150 CPU Cooler.LGA 1151 Cooler
- Intel CPU Fan.Model: RH-I30-26FK-R1 ,Noise Level: 22dBA±3 Fan Speed : 2200 RPM±10%
- Heatsink: 90 x 30mm Fan Size: 95 x 25mm Bearing Type : Alloy bearing Rated Voltage : DC 12V
- Noise Level: 22dBA±3 Fan Speed : 2200 RPM±10% Power Connector: 3-pin Theremal compound: Prepaste
- Package included: 1 x CPU Cooler Unit 1 x Backplate 1 x English User Manual
Core i5-4690K or i7-4790K at stock
The NH-U12S or Peerless Assassin 120 SE adds useful sustained-load and acoustic headroom without requiring an overclock.
Overclocking or workstation rendering
Prefer the Peerless Assassin 120 SE or NH-D15, subject to motherboard VRM quality, CPU voltage, silicon quality, airflow and clearance. No cooler recommendation can promise a particular clock speed or temperature without controlled testing.
CPU TDP is only a starting point. Intel describes it as an average power measure under a defined workload, not a guaranteed maximum heat output. Actual temperature also depends on power limits, voltage, ambient temperature, thermal paste, mounting pressure, fan curves and dust.
Fit-check before ordering
- Identify the exact CPU and motherboard. Confirm the board is not an OEM design with proprietary mounting.
- Read the case specification and compare its maximum CPU-cooler height with the cooler’s published height. The NH-U12S is 158 mm; the Peerless Assassin 120 SE is approximately 155 mm. The NH-D15 needs more room, especially if its front fan is raised.
- Measure RAM height. Tall RGB heat spreaders can overlap a dual-tower front fan; raising that fan increases cooler height.
- Inspect VRM heatsinks, the first PCIe slot and nearby motherboard components for width and installation access.
- Verify the exact package includes LGA1150/LGA115x hardware and check the seller’s return policy, particularly for old stock.
For a used Noctua cooler, documented upgrade support can add value. The NM-i115x kit upgrades certain older Noctua models to LGA115x sockets; eligibility still depends on the cooler model.
Best Value
- 【Fit for Flexibile Form Factors】An ideal choice for SFF builds or even full sized builds, coming in at 72mm in height compatibility is not an issue.
- 【Intel Optimized】Ensured compatibility with Intel LGA 1851/1700/1200/1156/1155/1151/1150.
- 【Infinity Mirror】Adding depth to lighting we installed an infinity mirror to the center hub of the fan for an extra effect.
- 【Non-Interference Design】No need to worry about choosing a specific kit of memory due to height requirement, thanks to the non-interference design there is no overlap from the cooler to the memory.
- 【Hydraulic Bearing Reliability】Built with reliability in mind the hydraulic bearing also excels with lowered noise during operation and enchanced thermal efficiency.
Installation procedure
- Shut down the PC, switch off the power supply and disconnect the mains cable.
- Remove the old heatsink and clean old paste from the CPU heat spreader and cooler base with suitable isopropyl alcohol and lint-free material.
- Install the manufacturer’s LGA115x backplate or mounting hardware exactly as shown in the installation manual.
- Apply the supplied thermal compound according to that cooler’s instructions.
- Seat the heatsink evenly and tighten screws gradually in an alternating pattern.
- Orient the fan so air travels through the heatsink toward the rear exhaust fan.
- Connect the fan to the motherboard’s CPU_FAN header.
- Start the PC, confirm the fan spins, and monitor idle and sustained-load temperatures. A single short reading is not a definitive test.
If temperatures are still high
- Verify the fan is on CPU_FAN and that any protective film was removed from the base.
- Recheck the bracket orientation, screw tension and heatsink contact.
- Inspect thermal-compound coverage and replace dried paste.
- Clean dust from the heatsink and restore a clear front-to-rear case airflow path.
- Check BIOS voltage and automatic overclock settings; excessive motherboard voltage can overwhelm an otherwise adequate cooler.
- Listen for a worn fan bearing and replace the fan if necessary.
Air cooling versus liquid cooling on LGA 1150
A quality air cooler is normally the better match for this platform: it has no pump to fail, no radiator to mount and little maintenance beyond dust cleaning and occasional paste replacement. An AIO can make sense when the case already has a suitable radiator mount, aesthetics are important, or a particular layout favors a radiator, but liquid cooling is not inherently superior for an older Haswell processor.
Buying new versus used
A used premium cooler can be excellent value if the savings reflect the age of the platform. Before buying, request photographs or a parts list confirming the LGA1150 brackets, inspect fins and heat pipes for damage or corrosion, check the fan for bearing noise, and budget for new thermal paste. Missing mounting bars can turn a mechanically compatible heatsink into an unusable purchase.
Final decision
Buy the Peerless Assassin 120 SE when your case, RAM and motherboard can accept a roughly 155 mm dual tower and you want the most cooling headroom per dollar. Pick the NH-U12S when fit certainty, quiet operation and long-term manufacturer support matter more than absolute value. Use a verified AK400-, Hyper 212- or equivalent single tower for most locked processors, and reserve the NH-D15 for genuinely demanding loads, overclocking or valuable future reuse. In every case, confirm the exact mounting kit and physical clearances before ordering.
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Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
