CPU Cooling – CompTIA A+ 220-901 – 1.6

Our CPU is one of the hottest devices in our computer, so it’s important to have an efficient cooling system. In this video, you’ll learn how heat sinks, on-board fans, case fans, liquid cooling, and passive cooling can be used to keep your system running at peak efficiency.

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As we use our computer, you’ll find that the components begin to get very hot. But fortunately, we’ve got a number of techniques that we can use to cool down your motherboard and keep it running at peak efficiency.

If you look closely at a motherboard or an electronics device, you’ll probably see a heat sink on some of the components. These are little metal devices. They are usually aluminum or copper based. And they’re designed to sit right on top of a very hot component and pull the heat out of that device into the fins that are on the top of the heat sink. These fins are creating a grid that is now increasing the surface area of that particular component, and we’re blowing cooler air past these, to be able to pull the heat off of the particular component and into the air.

Between the component and the heat sink is an adhesive we call thermal paste. This paste is also thermally conductive, so it helps facilitate the movement of heat from the component into the heat sink, and ultimately into the air that’s blown across the heat sink. As you can guess, some of these components get really hot, and obviously the heat sink will get hot as well. If you’ve just turned off a computer and you’re inside working on the components, be careful not to touch these, at least not initially. You may find that they will very easily burn your fingers.

If you’re building your own computer or you’re replacing the heat sink on an existing computer, then you want to be sure that you put the right amount of thermal paste right on the CPU itself. It doesn’t take a lot, just a small dab in the middle. When you place the heat sink on top, it will spread that out so that it’s evenly distributed in the bottom. And you’ll find that there are different kinds of heat sinks that take up different spaces on the CPU, but they’re all effectively doing the same thing. They’re pulling the heat off of the component and putting it into the air, where it can be cooled.

If you’re putting a heat sink on a CPU, it’s also very common to include a fan right on top of that heat sink, to help move the heat off even faster. And usually, you’ll even see power is very close by to the CPU. On this motherboard, it’s even marked CPU fan. This is going to allow you to move that heat even faster off of that very hot CPU and keep it as cool as possible.

Sometimes you may add a separate adapter card that has its own fans associated with it, so that it’s able to cool things even faster. These are going to take up quite a bit of room. You may find that a single adapter card may be taking up two or even three spots that would normally be on your motherboard. You very often see these on very high-end systems, especially graphics cards that are using a lot of CPU cycles and get very, very hot when you’re using them.

For these heat sinks to work properly, we want to be sure that we have cool air moving all the way through your case at all times. To be able to do that, we use case fans. These are fans that are physically connected to the case of your computer. And their job is to pull the cool air in and make sure that it is able to flow all the way through your computer case, and the warm air would come out on the other side.

That’s why the layout of your motherboard is so important. We want to make sure that there’s no wiring in the way, that there’s no components that are blocking the airflow, and we want to be sure that there’s nothing on the outside of your computer that is going to prevent any of that cool air from coming in and passing through the computer case.

There are many different styles and sizes of case fans, and you might want to change out a case fan in your computer to either make it more efficient or perhaps change the volume level. It’s also very common to see variable speed fans that connect to your motherboard, where the motherboard can increase the speed of the fan as the CPU and the motherboard become hotter. You may also find that there are different volume levels for fans. Some fans are designed to be quieter than others, and some fans are designed to be more efficient. And there’s usually a trade-off between how loud a fan is and how effective it is at cooling your system.

Another way of cooling your CPU is not with air but by using liquid. This is a very common way to cool components. We have liquid cooling in our cars. There are mainframe computers that use liquid cooling. So why not use liquid cooling to cool down our computer components? We usually see this on systems that are very high-end, that have high processing requirements. Maybe it’s a gaming computer, or it’s a system where you’re overclocking the CPU just to see how fast you can get the computer to go.

This liquid cooling is usually done in a closed system. You have the cool liquid that’s coming into a block that may be connected to your CPU. That liquid then heats up, and the hotter liquid is then sent away from the CPU to then be cooled. There is usually a fan or some type of radiator associated with the case that then cools down the liquid, and then it is rotated back through to begin the process again.

Many of our computing devices these days have no fans at all. All of the cooling is done in a passive form, usually using heat sinks. We often see this if it is a specialized device, like a video streaming device, a TV set-top box, maybe your satellite receiver. You’ll notice there’s no fans. And that’s because we’re watching television and we don’t want that extra noise in the room. These devices are specifically designed so that they are going to have this passive cooling process.

To be able to create these devices and know that they’re going to be cooled properly, they usually go through a series of tests. And that’s why these devices are built for one type of function only, because we want to be sure that they’re not going to overheat. These devices are usually using as little power as possible and taking advantage of heat sinks, so that they don’t need the noisy fans, and can simply use the normal room temperature air to keep everything in that device cool.