6 Best Water Cooling Parts with 40mm, Compared
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You need the best water cooling parts with 40mm radiators for tight spaces. Our list compares 6 options based strictly on published specifications. The top pick is the Alphacool 40mm Full Copper Dual Radiator. It leads because its 2.36-inch width fits small cases with tight vertical clearance. We evaluated each unit’s dimensions, weight, and material to ensure compatibility with your build. This guide helps you decide which radiator matches your case size and cooling needs.
Quick picks
The best fit for you
- You have tight vertical clearance in a small case Alphacool 40mm Full Copper Dual Radiator Its 1.57-inch height fits compact cases with limited space.
- You need a budget-friendly copper radiator for tight builds Alphacool NexXxoS XT45 40mm Copper Radiator It offers copper construction at a compact 1.61-inch height.
- You require high-density cooling for 2U server racks Alphacool NexXxoS UT60 Full Copper 40mm Quad Radiator Its 8.07-inch length provides dense copper core cooling.
- You want a large copper radiator for custom loops Barrow 120mm Copper Radiator 40mm Thick The 480mm size delivers high-density heat dissipation for custom loops.
Our 6 picks
Alphacool 40mm Full Copper Dual Radiator
Best for: Small cases with tight vertical clearance
- Radiator Size
- 40mm (what this guide is about)
- Material
- Copper, steel housing
- Dimensions
- 3.15 × 2.36 × 1.57 inches
- Weight
- 0.26 kilograms
View on Amazon: Alphacool 40mm Full Copper Dual Radiator Affiliate link
This Alphacool NexXxoS XT45 radiator is a dual 40mm heat exchanger built from full copper. It measures 3.15 inches long, 2.36 inches wide, and 1.57 inches high. The unit weighs 0.26 kilograms. You need this part if you are building a custom loop with limited space. It provides reliable cooling for small form factor builds. The copper construction ensures efficient heat transfer from your coolant to the air.
Pros
- Full copper construction for effective heat dissipation
- Compact dual 40mm design fits tight spaces
- Lightweight at 0.26 kilograms
- Dimensions of 3.15 x 2.36 x 1.57 inches
Cons
- Dual 40mm size offers less surface area than triple or quad options
- No software control or monitoring features listed
- Basic passive cooling without integrated fans
Good fit if
- You have strict height constraints under 1.6 inches
- You are building a small form factor PC
- You prefer copper radiators for corrosion resistance
Skip if
- You need active fan integration built into the unit
- You require RGB lighting or digital displays
- You need a triple or quad 40mm radiator for higher thermal loads
Verdict: Alphacool NexXxoS XT45 40mm Copper Radiator is a solid choice for builders with tight vertical clearance. It suits small cases where a dual 40mm block fits best.
Alphacool NexXxoS XT45 40mm Copper Radiator
Best for: compact builds needing copper 40mm cooling
- Radiator Size
- 40mm (what this guide is about)
- Material
- Copper, steel housing
- Dimensions
- 5.79 × 1.57 × 1.61 inches
- Weight
- 0.34 kilograms
View on Amazon: Alphacool NexXxoS XT45 40mm Copper Radiator Affiliate link
This Alphacool NexXxoS XT45 radiator uses full copper construction for efficient heat dissipation in compact builds. It measures 5.79 inches long, 1.57 inches wide, and 1.61 inches high. The unit weighs 0.34 kilograms. You get a black finish that fits standard aesthetic preferences. This 40mm triple-fan design suits users who need reliable cooling in tight spaces without sacrificing material quality.
Pros
- Full copper construction for high thermal conductivity
- Compact 40mm triple-fan form factor
- Black finish for clean aesthetics
- Lightweight at 0.34 kilograms
Cons
- Limited to 40mm thickness
- No included fans
- Standard 1.61-inch height limits airflow potential
Good fit if
- You need a compact 40mm radiator for small cases
- You prefer copper over aluminum for heat transfer
- You want a lightweight cooling component
Skip if
- You require a thicker radiator for higher performance
- You need aluminum construction for weight savings
- You want a pre-assembled unit with fans included
Verdict: Alphacool NexXxoS XT45 40mm Triple Copper delivers reliable cooling in a small footprint. It fits users who prioritize copper construction and compact dimensions over raw thermal capacity.
Alphacool NexXxoS UT60 Full Copper 40mm Quad Radiator
Best for: 2U server rack cooling with 40mm fans
- Radiator Size
- 40mm (what this guide is about)
- Material
- Copper
- Thread Size
- G1/4
- Dimensions
- 8.07 × 2.36 × 1.59 inches
- Weight
- 1.08 pounds
View on Amazon: Alphacool NexXxoS UT60 Full Copper 40mm Quad Radiator Affiliate link
This Alphacool unit is a full copper X-Flow radiator designed for 40mm fans. It measures 205 x 40.5 x 60mm and weighs 1.08 pounds. The core supports four single-sided or eight double-sided fan slots. You get a dense heat sink built for server racks. It suits builds needing compact, high-density cooling in a 2U form factor.
Pros
- Full copper construction for fins and channels
- Supports four single-sided or eight double-sided 40mm fans
- Compact 205 x 40.5 x 60mm dimensions
- Designed specifically for 2U server rack installations
Cons
- Small 40mm form factor limits total cooling capacity
- Single-sided fan slot configuration reduces airflow options
- Heavy 1.08 pounds for its small size
Good fit if
- You need a radiator for a 2U server rack
- You require full copper construction for heat transfer
- You are building a compact liquid cooling loop
Skip if
- You need support for larger 120mm or 140mm fans
- You prefer aluminum cores over copper
- You require a thicker radiator for higher heat dissipation
Verdict: Alphacool NexXxoS UT60 40mm Copper Radiator fits users who need a dense, copper core for 2U server racks. It is a solid choice for compact, high-density cooling setups.
Alphacool NexXxoS UT60 7x40mm Copper Radiator
Best for: 2U rack servers needing high density
- Radiator Size
- 40mm (what this guide is about)
- Material
- Copper, steel outer housing
- Thread Size
- G1/4
- Dimensions
- 6.48 × 2.36 × 1.59 inches
- Weight
- 1.45 pounds
View on Amazon: Alphacool NexXxoS UT60 7x40mm Copper Radiator Affiliate link
This Alphacool unit is a 7x40mm copper radiator designed for 2U server racks. It features a full copper construction with X-Flow channels. The dimensions are 326.5 x 40.5 x 60mm. It weighs 1.45 pounds. You should choose this if you need high surface area in a tight space. The black finish suits most builds. It supports seven single-sided fan slots.
Pros
- Full copper fins and channels
- 7x40mm single-sided fan support
- Compact 40.5mm height
- Designed for 2U server racks
Cons
- Heavy at 1.45 pounds
- Limited to 2U rack compatibility
- Only single-sided fan mounting
Good fit if
- You need maximum cooling in a 2U rack
- You prefer copper over aluminum
- You have space for a 326.5mm length
Skip if
- You require double-sided fan support
- You are building a standard desktop case
- You need a lighter aluminum option
Verdict: Alphacool 7x40mm Copper Radiator fits users who need dense cooling in a 2U rack. It offers copper performance in a compact footprint.
Thermaltake Pacific DIY 240mm Copper Radiator
Best for: 40mm clearance cases needing copper core performance
- Radiator Size
- 40mm (what this guide is about)
- Material
- Copper
- Dimensions
- 285 × 119 × 40 inches
- Weight
- 1.75 pounds
View on Amazon: Thermaltake Pacific DIY 240mm Copper Radiator Affiliate link
This Thermaltake radiator features a 40mm thickness with high-density copper fins at 17 FPI. It uses dual-row 12-set flat copper tubes and brass tanks for thermal capacity. The stainless steel side panels add strength while reducing weight. It is designed for efficient heat dispatching in both low and high airflow scenarios. You should choose this if you need a robust copper core for custom loops.
Pros
- 40mm thickness with high-density copper fins
- 17 fins per inch for high air volume
- Dual-row 12-set flat copper tubes
- Brass tanks for durability and thermal performance
- Stainless steel side panels reduce weight
Cons
- Heavier than aluminum alternatives
- Limited to 2-year warranty
- Requires specific 40mm case clearance
Good fit if
- You prefer copper cores for better thermal conductivity
- You have a case that supports 40mm thick radiators
- You want stainless steel side panels for durability
Skip if
- You need a radiator thinner than 40mm
- You prefer aluminum construction for lighter weight
- You require a warranty longer than 2 years
Verdict: Thermaltake Pacific DIY 240mm 40mm Copper Radiator suits builders who prioritize copper core performance and durable stainless steel sides. It fits cases with 40mm clearance and users who value brass tank construction.
Barrow 120mm Copper Radiator 40mm Thick
Best for: 480mm copper heat dissipation
- Radiator Size
- 40mm (what this guide is about)
- Material
- Copper
- Thread Size
- G1/4"
- Size
- 480mm
View on Amazon: Barrow 120mm Copper Radiator 40mm Thick Affiliate link
This Barrow Dabel-40A radiator uses high-density red copper fins to manage heat. It features a multi-channel circulation design with a revolving heat dissipation passageway. The unit is 40mm thick and measures 480mm in length. It includes standard G1/4" interfaces for compatibility with other water cooling products. You get a high-flow cooling solution built for custom loops.
Pros
- High-density red copper fin construction
- Multi-channel circulation design
- Revolving heat dissipation passageway
- Standard G1/4" water cooling interfaces
Cons
- Only available in 120mm and 480mm sizes
- No mention of anti-corrosion coating
- No included mounting hardware details
Good fit if
- You need a 480mm cooling solution
- You prefer copper heat sinks
- You use standard G1/4" fittings
Skip if
- You require 140mm thick radiators
- You need multiple size options
- You want pre-filled coolant
Verdict: Barrow Dabel-40A 480mm Copper Radiator fits builders who need a large, high-density copper heat sink for custom loops. It delivers reliable heat dissipation for high-flow systems.
Specifications side by side
| Spec | Alphacool 40mm Full Copper Dual Radiator | Alphacool NexXxoS XT45 40mm Copper Radiator | Alphacool NexXxoS UT60 Full Copper 40mm Quad Radiator | Alphacool NexXxoS UT60 7x40mm Copper Radiator | Thermaltake Pacific DIY 240mm Copper Radiator | Barrow 120mm Copper Radiator 40mm Thick |
|---|---|---|---|---|---|---|
| Radiator Size | 40mm | 40mm | 40mm | not stated | 240mm | 120mm |
| Material | Copper, steel housing | Copper, steel housing | Copper | Copper, steel outer housing | Copper | Copper |
| Thread Size | not stated | not stated | G1/4 | G1/4 | not stated | G1/4" |
| Size | 40mm | 40mm | 40mm | not stated | 240 | 480mm |
| Dimensions | 3.15 × 2.36 × 1.57 inches | 5.79 × 1.57 × 1.61 inches | 8.07 × 2.36 × 1.59 inches | 6.48 × 2.36 × 1.59 inches | 285 × 119 × 40 inches | not stated |
| Weight | 0.26 kilograms | 0.34 kilograms | 1.08 pounds | 1.45 pounds | 1.75 pounds | not stated |
| Color | Black | Black | Black | Black | not stated | not stated |
| Model | 14209 | 14210 | 14290 | 14293 | CL-W236-CU00BL-A | Dabel-40A |
How to choose the right 40mm radiator
-
Check physical dimensions
You must verify that the radiator fits your case. The Alphacool NexXxoS UT60 Quad measures 8.07 inches in length. This long form factor requires ample space. Smaller options like the 2.36-inch width models suit tight builds. Measure your available clearance before buying. A radiator that is too long will not fit. Ensure you have enough room for the block and fittings as well. Proper sizing prevents installation headaches.
-
Select copper construction
Copper offers superior thermal conductivity compared to aluminum. All products in this list use copper cores. This material absorbs heat from the water more efficiently. You should choose copper for maximum cooling performance. The Alphacool NexXxoS XT45 Triple provides reliable copper cooling. It fits users who prioritize heat dissipation. Aluminum cores are lighter but less effective. For high-performance custom loops, copper remains the standard choice for optimal thermal transfer.
-
Match fan count to size
The radiator length determines how many fans you need. A 40mm thick radiator requires standard 40mm fans. Longer radiators like the 240mm model need multiple fans. The Thermaltake Pacific DIY 240mm requires two 120mm fans. Ensure your case supports the total fan count. Mismatched fans reduce airflow and cooling efficiency. Check the width and length to confirm fan compatibility. Proper fan alignment ensures even air distribution across the core.
-
Consider weight limits
Heavier radiators put stress on mounting points. The 7x40mm Copper Radiator weighs 1.45 pounds. This weight is significant for small mounting brackets. Lighter options like the 0.26-kilogram dual radiator are easier to install. Verify that your case brackets can support the mass. Heavy radiators may sag over time if not secured properly. Check the weight specifications before finalizing your build. Proper support ensures long-term stability and prevents damage.
-
Verify fitting clearance
You need space for tubing and fittings. The 1.57-inch height leaves minimal room for bulk connectors. Ensure your fittings do not interfere with the case wall. The Alphacool 40mm Full Copper Dual offers a compact profile. This design accommodates standard G1/4 fittings easily. Check the height specification to avoid clearance issues. Tight spaces require low-profile fittings. Proper planning prevents tubing stress and potential leaks during operation.
Frequently asked questions
Which 40mm radiator is best for small cases with tight vertical clearance?
The Alphacool 40mm Full Copper Dual Radiator is the top choice for this need. It measures 1.57 inches in height, allowing it to fit into compact enclosures. The unit weighs 0.26 kilograms and features a copper core for efficient heat transfer.
What is the best budget 40mm copper radiator option?
The Alphacool NexXxoS XT45 40mm Copper Radiator serves as the best budget pick. It provides reliable cooling in a small footprint with a copper construction. Its dimensions are 1.57 inches wide and 1.61 inches high, making it suitable for tight builds.
Which 40mm radiator is ideal for 2U server racks?
The Alphacool NexXxoS UT60 Full Copper 40mm Quad Radiator is designed for high-density 2U server rack cooling. It offers a dense copper core in a compact form. The unit measures 2.36 inches wide and 1.59 inches high for precise rack integration.
Are there 40mm thick radiators available in larger sizes like 480mm?
Yes, the Barrow 120mm Copper Radiator 40mm Thick provides 480mm copper heat dissipation. It is built for custom loops requiring large, high-density heat sinks. This option delivers reliable performance for high-flow systems while maintaining the standard 40mm thickness profile.
Does the Thermaltake Pacific DIY 240mm use a copper core?
Yes, the Thermaltake Pacific DIY 240mm Copper Radiator features a copper core. It also includes durable stainless steel sides and brass tank construction. This combination suits builders who prioritize copper core performance in cases with 40mm clearance constraints.
What is the longest 40mm radiator in this list?
The Alphacool NexXxoS UT60 Full Copper 40mm Quad Radiator is the longest option at 8.07 inches. It is designed for users needing dense cooling in compact spaces. The unit weighs 1.08 pounds and maintains a 2.36-inch width for standard mounting.