RTX 4090 Cooling Guide: Air vs Liquid for Top CPUs

RTX 4090 Cooling Guide: Air vs Liquid for Top CPUs

The newly released Nvidia RTX 4090 graphics card brings exceptional performance and visual fidelity to the latest games and creative applications. However, with its beefy 450W TDP, the RTX 4090 runs extremely hot and requires robust cooling to maintain stability and maximize boost clocks. 

In this guide, we’ll compare air and liquid cooling solutions to help you keep your RTX 4090 running cool when paired with today’s top CPUs.

Air Coolers: A Cost-Effective RTX 4090 Cooling Option

Air coolers offer a simple and affordable way to tame the RTX 4090’s heat output. High-end air coolers like the Noctua NH-D15 chromax black or Dark Rock Pro 4 feature dense fin stacks, six copper heat pipes, and two large 140mm fans to dissipate up to 250W.

The key advantages of air coolers:

  • Lower cost – High performance air coolers cost $80-$100, a fraction of the price of liquid coolers.
  • Easy installation – Air coolers use simple mounting mechanisms and removable fans for easy installation and maintenance.
  • Reliability – With no pump or chance of leaks, air coolers are worry-free and last for years.

However, air coolers do have some limitations:

  • Limited heat dissipation – Even the best air coolers can only dissipate around 250-300W, which may not be enough for an overclocked RTX 4090.
  • Bulky size – Large twin or single tower designs take up a lot of space around the CPU socket.
  • Motherboard compatibility – Tall heatpipe towers can interfere with top-mounted 8-pin CPU power connectors on some boards.

Overall, air coolers like the Noctua NH-D15 or DeepCool Assassin III are great options for running the RTX 4090 at stock settings and mild overclocks in roomy PC cases. Just make sure to choose a model rated for at least 250W TDP.

Liquid CPU Coolers: Maximum Cooling for Overclocked RTX 4090 Setups

For pushing the RTX 4090’s OC farther or pairing it with an overclocked top-tier CPU like the Core i9-13900K, a high performance liquid cooler is recommended. A 280mm or 360mm radiator with two or three fans can dissipate 300W+ to keep your overclocked components cool.

Some benefits of liquid coolers:

  • Superior cooling capacity – 360mm models with triple 120mm fans can dissipate over 300W. Ideal for OC’d setups.
  • Cleaner builds – Only the radiator and fans mount in the case while the pump rests on the CPU. This reduces clutter around the motherboard.
  • Redesigned cold plates – New cold plates like Corsair’s optically clear caps improve thermal transfer and cooling on Alder Lake CPUs.
  • Quieter performance – Larger radiators paired with bigger, slower-spinning fans can achieve the same cooling at lower noise levels.

The downsides of liquid cooling include:

  • Higher costs – Entry-level 240mm coolers start around $120, with 360mm models going up to $180.
  • Risk of leaks – Though rare, a failed fitting or cracked tubing can lead to leaking coolant in your PC.
  • Pump noise – Some liquid cooler pumps emit a faint buzzing sound, though models like the NZXT Kraken X73 use near-silent pumps.

For cooling even the most heavily overclocked RTX 4090 and Core i9-13900K combo, we recommend at least a 280mm cooler like the DeepCool LS520EX. Stepping up to a triple 120mm radiator model like the Lian Li Galahad AIO360 provides the ultimate cooling capacity for pushing both GPU and CPU clocks to the limit.

Best Air Coolers for the RTX 4090

Here are our top air cooler recommendations for use with the RTX 4090:

Noctua NH-D15

  • 6 heatpipes, dual 140mm fans
  • 250W TDP
  • 165 x 150 x 135mm (HxWxD)
  • RAM clearance: 32mm

Dark Rock Pro 4

  • 7 heatpipes, dual 135mm fans
  • 250W TDP
  • 163 x 137 x 135mm
  • RAM clearance: 40mm

Thermalright Peerless Assassin 120 SE

  • 6 heatpipes, single 120mm fan
  • 250W TDP
  • 155.4 x 130 x 98mm
  • RAM clearance: 35mm

DeepCool AK620

  • 6 heatpipes, dual 120mm fans
  • 250W TDP
  • 158.5 x 130 x 98mm
  • RAM clearance: 53mm

Scythe Fuma 2

  • 6 heatpipes, dual 120mm fans
  • 250W TDP
  • 154.5 x 130 x 99mm
  • RAM clearance: 32mm

Any of these air coolers can sufficiently tame the RTX 4090 at stock settings while generating minimal noise. The NH-D15 and Dark Rock Pro 4 offer the best cooling capacity for mild overclocking.

See Also: Making the Most of Resizable BAR with RTX 4090 and CPU Pairing

Best Liquid Coolers for the RTX 4090 and Overclocked CPUs

For taking your RTX 4090 and CPU overclocks to the extreme, we recommend these top-rated liquid coolers:

Corsair iCUE H150i Elite

  • 360mm triple 120mm fans
  • 400W+ TDP
  • 30mm thick radiator
  • Copper cold plate with micro-channels
  • 16 addressable RGB LEDs

NZXT Kraken X73

  • 280mm dual 140mm fans
  • 300W+ TDP
  • 27mm aluminum radiator
  • Copper cold plate
  • RGB infinity mirror cap

ARCTIC Liquid Freezer II 280

  • 280mm dual 140mm fans
  • 300W+ TDP
  • 38mm aluminum radiator
  • Copper cold plate
  • Fully sealed water cooling system

Lian Li Galahad AIO360

  • 360mm triple 120mm uni-fans
  • 32mm aluminum radiator
  • 300W+ TDP
  • Addressable RGB lighting

EK EK-AIO Elite 360 D-RGB

  • 360mm triple 120mm fans
  • 16 addressable RGB LEDs
  • EK-Vardar fans for high static pressure
  • Expandable cooling for custom loops

While more expensive, these 280mm and 360mm liquid coolers will enable pushing your RTX 4090 and flagship CPU to new performance heights. Their extra cooling capacity gives you thermal headroom to maximize clocks and framerates.

Additional Cooling Tips for the RTX 4090

Beyond selecting the right CPU cooler, here are some additional tips to ensure your RTX 4090 runs cool:

  • Use a well-ventilated PC case like the Lian Li Lancool III or Phanteks P500A. Open mesh front panels promote better airflow.
  • Set up optimal case fan configurations with at least two 140mm intakes and one 120mm rear exhaust. This creates positive pressure and removes hot air.
  • Undervolt your RTX 4090 to reduce its heat output. AMD Ryzen CPUs can also be undervolted for cooler operation.
  • Enable GPU vertical mount if supported by your case. This places the hot GPU side panel fans instead of battling your CPU cooler.
  • Replace stock thermal paste on the GPU and CPU with a premium compound like Thermal Grizzly Kryonaut for a few degrees better cooling.
  • Turn up fan speeds if needed, though aim to balance noise and thermals. 82°C or lower is ideal for GPU/CPU while gaming.


The bottom line is that effective cooling is critical for the RTX 4090 to prevent thermal throttling and achieve maximum performance. While high-end air coolers can sufficiently tame the heat from a stock RTX 4090, stepping up to a 360mm all-in-one liquid cooler with a thick radiator and triple 120mm fans is recommended for heavy overclocking and pairing with an overclocked top-tier CPU. Additionally, optimal case airflow, under-volting components, upgrading thermal paste, and custom fan curves will further improve cooling capacity. With the right cooling setup tailored to your budget and goals, both air and liquid cooling can effectively cool even the hottest RTX 4090 build. Careful cooling configuration is the key to unlocking the RTX 4090’s full performance potential.

Sufyan Mughal
Sufyan Mughal, is a Tech and Gaming nerd. He developed his passion during the college days and is now working passionately to make his dreams come true. He mostly likes Gaming but is also a master of Tech. His knowledge has served many people around him. He mostly likes to be alone to gain as much knowledge as he can which makes him a true master of Tech World.