What is a CPU cooler and how does it work?

The role of the cooler is to lower the temperature generated by your processor. Through its contact with the processor, it absorbs the heat, which is then dissipated through pipes that remove it from the processor.

Active vs Passive Coolers

Active Coolers: These are the most popular. They have a fan to remove the heat trapped in the pipes, pushing it towards the case air vents.

Passive Coolers: They do not have fans and rely solely on the conductivity of the metal.

For effective heat transfer from the processor to the cooler, you apply a small amount of thermal paste at the point where the two devices meet, to speed up the heat transfer. Most coolers on the market include this paste in their packaging, while some already have it pre-applied so you don't have to do it yourself.

Skroutz Tip: Changing your cooler? Attention! Every time you need to remove the cooler from your processor for any reason, you need to reapply the thermal paste at the contact point before reinstalling it.

Compatibility: Will it fit my motherboard? (The so-called Sockets) 

Before you buy anything, you need to know your motherboard's "socket," meaning the "slot" where the processor sits. Think of it like your shoe size.

• If you are building a brand new computer, you most likely have a LGA 1700 or LGA 1851 socket if you chose Intel, or AM5 if you chose AMD.

• If you are upgrading an older PC, you might have LGA 1200 / 1151 (for Intel) or AM4 (for AMD). What to do: Check the specifications of the cooler you are interested in. Under "Supported Sockets," it must definitely list your number, otherwise it won't fit!

TDP: How much heat can the cooler handle? Beware of the trap!

Every processor generates heat, which is measured in Watts and is called TDP. Companies often state: "This processor is at 65W." But be careful: Modern processors, when "pushed" (e.g. when you play demanding games), suddenly ramp up. So, a 65W processor can easily produce 150W of heat or even more!

What to do: Get a cooler that can handle much more Wattage (TDP) than what your processor's manufacturer states. If your processor says 105W, choose a cooler that can cool 200W+. This way, you will always have low temperatures without the fan sounding like an airplane.

Air Cooling or Water Cooling? What should I choose? 

There is a big myth here: "Liquid systems are always better." Wrong!

• Air Cooling (Fan with metal heatsink): This is the most classic, affordable, and "immortal" solution. It almost never breaks down (only if the fan fails, which is easy to replace). A huge, high-quality air cooler can lower temperatures better than a cheap, small water cooler! Its only downside? It takes up a lot of space.

• Water Cooling (AIO - Liquid cooler): It looks stunning, looks perfect inside the case with its lights, and leaves free space around the processor. Good and large water coolers (240mm or 360mm) are the "kings" for keeping very powerful computers ice-cold, but they cost more.

Will it fit in my system?

The cooler is the component most often returned to stores because... quite simply, "it didn’t fit"! Before you click "Buy", do these quick checks:

• For Air Cooling (Height and RAM Clearance): Check your case’s specifications for the "Maximum Cooler Height". If your case supports up to 160 millimeters (mm) and the cooler you want is 165mm, the side glass won’t close! Also, if the cooler is very bulky, it might interfere with your RAM (known as RAM Clearance), especially if you have RAM with "tall" heatsinks.

• For Liquid Cooling (Case Thickness): Make sure your case has mounting points for the radiator. But be careful: Keep in mind that the radiator together with the fans is about 5.5 centimeters thick in total. Make sure they won’t "collide" with your motherboard at the top of the case.

Do I need extra thermal paste?

Thermal paste is that gray "cream" that goes between the processor and the heatsink to transfer heat. The good news? Almost all new heatsinks already have it pre-applied at the factory on their base, or include a small tube inside the package. So you don't need to buy extra, unless you want to chase perfect temperatures with some specialized paste from the market.

In conclusion

Now that you know the essentials about CPU coolers, you are ready to take your build to the next level.