Cooler Master Seidon 120V 120mm CPU Liquid Cooler

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Quoting product code: A10NN


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About this product


  • Factory filled with coolant, sealed and pressure tested so you can use it almost immediately
  • Compatible with a range of sockets, such as Intel LGA 2011-3, 2011, 115x and AMD FM2+, AM3+
  • Supplied with a 120mm fan which spins at a maximum 2400RPM, producing 40dBA of noise

Product overview

• Factory filled with coolant, sealed and pressure tested so you can use it almost immediately
• Compatible with a range of sockets, such as Intel LGA 2011-3, 2011, 115x and AMD FM2+, AM3+
• Supplied with a 120mm fan which spins at a maximum 2400RPM, producing 40dBA of noise
• At max RPM, the fan moves 86.15 cubic feet per minute (CFM) of air, producing exceptional airflow around your system
• Fan is fitted with a 4-pin fan connector, which is backwards compatible with 3-pin fan connections
• Cooling block has a standard 3-pin fan connector for connecting to almost any motherboard
• Manufacturer part number: RL-S12V-24PK-R1

Special features
• Blue LED light indicates when the cooler is operational
• Features pulse width modulation (PWM), which allows for full control over the exact fan speed

Will this be the right cooler for me?
If you’re looking for a compact and ready to go water cooling system for your rig, then this Seidon 120V CPU liquid cooler would be a great choice. Complete with radiator, fan and pump built into the water block, it is all ready to go. The included fan can spin up to a maximum 2400RPM, which produces 40dBA of noise, 4.16mm/H2O of static pressure and moves 86.15 cubic feet per minute (CFM) of air, to keep the coolant and your CPU nice and cool.

A blue LED light on the water block lights up when the water cooler is in operation, supplying you with an indication when it is on. Ultra-fine micro-channels on the cold plate maximises the water contact surface for quick dissipation of heat, with the pump generating 23dBA of noise.

How do I change the fan speed?
The fan supports pulse width modulation (PWM) for increased speed control, so you can adjust the speed to as low as 600RPM, from 2400RPM. This reduces the amount of noise emitted to a quiet 19dBA, but also lowers the airflow produced to 19.17CFM. With such a wide RPM range, you can always fine tune the fan speed to find the right balance between fan noise and performance.

What is this compatible with?
Supplied with a universal tool-free mounting system, you are provided with back plates, screws, stand-offs and thermal compound, for you to affix this CPU liquid cooler to almost all motherboards. This particular water cooler is compatible with both Intel and AMD sockets, such as Intel LGA 2011-3, 115x (1156, 1155, 1151, 1150) and AMD AM3+ and FM2+.

Rated 5 out of 5 by from Happy to recommend Very pleased with this CPU cooler indeed. Had been having major problems with the very similar Corsair Hydro H60 system it has replaced. Apart from the Corsair not coming with everything needed to fit to my AM3 it has failed after just a few months. The Coolermaster came with everything needed to fit, including the motherboard backplate that the Corsair lacked. It is also less costly and the fan seems far more efficient keeping my CPU at a constant 41C. The fitting instructions were also very clear and it has an attractive blue LED to show it is working.
Date published: 2014-09-09
Rated 4 out of 5 by from I cut my temperatures in half. I do a lot of CGI rendering which has the CPU running all cores at 100% for 24 hours at a time. With the stock cooler the temperatures would rise to 98°C and I'd have to take the side cover off the tower and aim a desktop fan inside to lower temperatures down to a safer 75°C. With the Cooler Master Seidon 120V the temperatures are now only 55°C at 100% load and idle is only 28°C. My CPU is an Intel i7 4770. Only problem with Maplin was I ordered online and chose to collect in store. After a week they never told me the item had arrived in store and I only found out when I went down there to see where it was. It was just sat on the shelf.
Date published: 2016-11-04
Rated 5 out of 5 by from Best CPU Cooler Made This Is Well Made Bought For MY Intel Gaming System And Was Very Easy To Install Keeps My System Very Cool. I Am Thinking Of Buying A Second One For My Other PC I Have. Well Recommended Indeed. Thanks To Maplin For Selling This Amazing Product.
Date published: 2014-10-23
Rated 4 out of 5 by from excellent for a budget water cooler Brilliant cooler. Max temp @4.5GHz (i5 2500K) was 64 degrees. Idle is around 22-26. 1st booted up in the morning at was 17 degrees. Only downfall is the noise that the pump makes. Makes a faint buzzing noise. Other then that, brilliant.
Date published: 2014-12-03
Rated 4 out of 5 by from Cools better than silverstone and only £40 The only thing I can moan about is the stiff pipe, it would of been better if it was rubber. Pump=9/10 Radiator=7/10 Fan=9/10 Pipe=5/10 but the cooling 10/10
Date published: 2017-02-27
Rated 1 out of 5 by from Rubbish I bought this thinking it was going to be good and last a few years, but it lasted less then a year and the water pump broke. DO NOT BUY THIS PRODUCT!!!!!!
Date published: 2016-09-19
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Manufacturer part number RL-S12V-24PK-R1
Manufacturer Cooler Master
Product type CPU liquid cooler
For use with CPU
Colour Black
LED colour Blue
Fan diameter 120 mm
Included fan quantity 1
Noise level 19 dBA to 40 dBA
Airflow 19.17 CFM to 86.15 CFM
Static pressure 0.31 mm H20 to 4.16 mm H2O
Rotation Speed 600 RPM to 2400 RPM (PWM)
Fan Bearing Rifle
Adjustable fan speed Yes
Mounting kit included Yes – mounting screws and back plates
Fan power
Power wattage 3.6 W
Operating voltage 12 V
Power draw 0.3 A
Power connector 4-pin
Compatible sockets – Intel Intel LGA 2011-3, 2011, 1366, LGA 115x (1156, 1155, 1151, 1150), 775
Compatible sockets – AMD AMD Socket FM2+, FM2, FM1, AM3+, AM3, AM2
Compatible monitoring software N/A
Other features
Pump noise level 23 dBA
Cooling block – power connector 3-pin
Tubes 2 x 315 mm long tubes
Width 120 mm
Depth 25 mm
Height 120 mm
Width 154 mm
Depth 27 mm
Height 119 mm
Cooling block
Width 62 mm
Depth 36.4 mm
Height 62 mm
Total – fan and radiator
Width 154 mm
Depth 52 mm
Height 120 mm
Cold plate material Copper
Radiator material Aluminium
Manufacturer warranty 2 years
Cables included and length Power cables connected
Package contents
Water cooling system (fan, radiator and water block)
Universal mounting system (brackets/back plates, screws, stand-offs and thermal compound)

Does any inevitable know if it will fit am4 as am3 and am4 are pretty much the same layout on a motherboard

Asked by: Dann
If the cooler uses the stock amd mountings - ie the spring loaded bracket - it will fit. If it uses a custom backplate & custom mounting system it won't fit. Cooler Master should be able to offer you an AM4 mounting kit if it doesn't fit without it
Answered by: Dale
Date published: 2017-04-12

Is this a cpu fan? If yes is it suitable for the intel i5 660k? Thanks

Asked by: B Cos
on the assumption that you mean Intel i5 6600K, then yes it will be fine. The i5 6600k fits into a LGA1151 socket. This cooler is designed to fit the following sockets. *Compatible with a range of sockets, such as Intel LGA 2011-3, 2011, 115x and AMD FM2+, AM3+ LGA115x means it will fit any of the 115 sockets such as 1151 & 1155
Answered by: Les
Date published: 2017-03-02

Will this be compatible with a stock fm2 Socket? 

Asked by: Ryan
Compatible sockets – AMD Socket FM2+, FM2, FM1, AM3+, AM3, AM2
Answered by: James
Date published: 2016-12-29

Is this the Version 2?

Asked by: Tumble
Yes, it is.
Answered by: Dominic
Date published: 2016-11-15

Will the coolant evaporate with the heat coming from the cpu so that I will need to replace the product in time or does the coolant last quite a long time.

Asked by: Andrew
No this is a sealed system
Answered by: Les
Date published: 2016-10-06

Does the coolant need to be topped up after a long period of usage or will i need to replace all the product.

Asked by: Andrew
The coolant in this product cannot be topped up.
Answered by: Dale
Date published: 2016-10-05

will this fit on an i3 4130 processor many thanx

Asked by: odin
Yes this should fit fine.
Answered by: Billy
Date published: 2015-10-28

Will this system handle an FX6300 overclocked 6 core processor

Asked by: Heidi
Unfortunately we are unable to guarantee full compatibility for this item in your intended application.
Answered by: Dominic
Date published: 2015-07-17
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