CPU Cooling – CompTIA A+ 220-1001 – 3.5


Our CPUs produce a lot of heat, and we have many options for keeping our systems cool. In this video, you’ll learn about case fans, heat sinks, liquid cooling, and more.

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With any computing device, keeping the device cool is always one of the biggest challenges. In this video, we’ll look at your options for CPU cooling. When you turn on your computer, you can hear the fans starting up. And if you put your hand near the front of your computer, you can probably feel the air being pulled through the system.

This is the primary method that most computers use to cool the inside of this computer case. Cool air is pulled through the front. The air is then warmed up as it’s passing over the CPUs and the warm components inside of the computer. And that warm air is sent out the top and the back of the system. This is another reason why it’s so important to make sure that you’re not blocking any of these slots and that you have good airflow through the system.

The layout of the motherboard also becomes important. You want to be sure that you don’t have a lot of cables or components that are blocking the air from blowing through. And you want to check to see where your components are placed in the system. It might make more sense to put larger cards lower in the system or perhaps make sure cables are moved out of the way to allow good airflow.

You have a lot of options for cooling your CPU and the other parts of your system. There’s different fans, different speeds, and different volumes that you can choose to design the perfect cooling system for you. Sometimes the cooling is part of the adapter card itself. This particular adapter card has a fan right in the middle. Looks like it’s sitting right on top of some heat sinks on this high end graphics card.

This can obviously be a little bulky. This particular card is taking two slots. And a lot of that width is because there is a fan built into the card. This is very common to see on devices that have their own integrated processors, such as high-end graphics cards.

If you have a full-sized computer case, then you probably have one or more fans inside of it that are pulling the air through. These fans come in standard sizes. You may see 80-millimeter, 120-millimeter, or even 200-millimeter fans.

And if these fans are connected to a fan controller or your motherboard supports fan controller functions, you may also find that these fans will run at different speeds. As the temperatures get hotter inside the computer, the speeds of the fan will go faster. And you may find that different fans have different amounts of noise that they’ll make. There are some fans that are specially designed to be very quiet and other fans that are designed to be more efficient, but they may be a bit louder inside of your case.

As the fans are pulling air through your system, that air is passing over a heat sink. A heat sink is specifically designed to take the heat from a processor and dissipate it up through the metal conductors that are in that heat sink. This is usually a copper or an aluminum alloy that is able to conduct heat very efficiently. As you can see with this heat sink, we’re taking a very flat area, and we’re creating a much larger surface area that we can use to then pull the air through. And that makes it very easy to transfer the heat from the heat sink itself into the air that’s passing through your computer.

Another important component when you’re adding a heat sink to a processor is this thermal paste that you can almost see between the heat sink at the processor. This creates a good contact between the two. And it allows for an efficient transfer of heat from the CPU into the heat sink.

And a good safety tip if you’re working inside of your computer, you’ve just turned the computer off, you may find that these heat sinks still have quite a bit of heat on them. So be very careful about touching them, especially if you’ve just been using your computer.

We’re putting more and more of our computing components right next to our televisions or in rooms where normally it’s very quiet. And those components sometimes will have no fans at all or will use passive cooling. So there’s no noise as that device is sitting on the shelf right next to where you’re watching television.

These are usually very specialized devices– a streaming media server, a satellite receiver, or a TV set top box. The functions inside of these are obviously very limited, which means that they have been thoroughly tested to make sure that they’re able to perform properly but also stay cool at the same time. If you were to look inside of these devices, you would find that many of the components have been specially engineered to be lower voltage, and therefore to put off less heat.

And you’ll also find a number of heat sinks inside of these devices. The heat sink doesn’t make any noise. But it still allows you to dissipate some of that heat out through the air.

If you’re installing a heat sink onto a CPU, you first need to make sure you have the proper amount of thermal paste. A good rule of thumb is to put thermal paste, or this thermal grease, that’s about the size of a pea. And when you place the heat sink on top of it, it will flatten out to have an even distribution on top of the CPU.

If you look inside your computer, you may see many different kinds of heat sinks. This one happens to be red with its own style. But there may be other colors such as gold or silver as well.

The CPU that’s in your computer is probably the component that’s creating the most amount of heat. So it’s not unusual to not only see a heat sink on top of that CPU, but to also see a fan on top of the heat sink. This is going to improve the amount of cooling that we get from our heat sink and keep the system that much cooler.

In fact, you’ll often see right next to the CPU is a power connection that is specifically designed for the fan that sits on top of this heat sink. You have lots of options for these heat sinks, especially the ones for CPUs. Here’s one that is very large.

And it extends up vertically instead of horizontally. This means you can have a very large heat sink that doesn’t get in the way of the other components on the motherboard. And this also means that you can have larger fans, which will decrease the amount of noise being caused by these cooling systems.

Instead of using air to cool our computers, we could just as easily use liquid. This is the same process we use to cool our automobiles and cool mainframe computers. And it’s usually designed for a computer systems that are higher-end.

If you are a gamer, or you perform higher end video editing, or you’re someone who likes to overclock your system, you may want to use liquid cooling as a more efficient way to cool things down. The heat sink that you would use for a liquid cooling system looks a little bit different. You have the cooler liquid coming into the heat sink.

That liquid is then heated up as it passes over. And then the hotter liquid is then sent out the other side. In the back of your computer is usually a radiator and a fan that cools down the liquid so that you can then send it through the system again.