CPU Cooling Techniques – CompTIA A+ 220-801: 1.6

Your CPU creates a large amount of heat, and it’s important that your computer’s cooling system is working to keep your CPU at a reasonable working temperature. In this video, you’ll learn about how heat sinks, cooling systems, and liquid cooling systems can keep your processors cool.

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A very common method to cool the components inside of our computers is something called a heat sink. This is a copper or aluminum piece that is put on top of a very hot component. Usually these are the very hot chips that are right on our motherboards. And as they heat up, all of the heat is pulled up through this heat sink.

And because we have all these little holes that are being pulled here as the air blows through it, it is also cooling the top of the heap sink. So we’re able to dissipate that heat and get rid of it outside of our computing case. You can see that the surface area is very large. We take it from that very flat area and extend it up through these little fins, and let that air flow through.

One important piece of this is that underneath this heat sink where it is connecting to that very, very hot chip, we put a thermal grease that is designed to keep a good connection between the heat sink and the processor itself. If that particular connection is not very good, then the heat is not going to dissipate well.

And that thermal grease is designed to keep a very good connection between the heat sink and the component itself. One important safety tip is if you’re doing a lot of processing on your computer, these components are getting very hot. And because the heat sink is dissipating that heat, it also gets very hot.

So if you’re working inside of a computer that you’ve just turned off, be careful, because these heat sinks can get very, very warm to the touch. In your computer, there’s probably more than one heat sink that you have. You can see a heat sink that might be on a main processor. There’s other heat sinks that might be on a north bridge, and other components themselves may have other heat sinks.

These look kind of interesting in that they have these little fins come up, and they almost look like flames coming up through there for a little bit of a design right there on your motherboard. But they’re all performing the same function. They’re taking the heat off of these components that are on the motherboard itself, and pulling that heat right off so that the air can cool it as it goes by.

It’s also not uncommon to put heat sinks right on top of your processors, and on top of the heat sinks, you might even have fans that are pulling that air right off of the heat sink itself and sending it out of the case. So you may have fans on the case that are connected physically to the heat sinks themselves to add that much more cooling capability to those components.

Sometimes you’ll see an adapter card that has on it its own set of fans, especially if it’s something like a video card. These can be kind of bulky because you not only have the adapter card itself, but you’ve now put a fan inside of it to make sure that it gets its own cooling as well.

It’s almost always seen on these high end graphics cards, or other types of cards that are performing very, very high end processes, because those components tend to get very, very hot. If you don’t know how the air flows through your particular computer, you should take a look at it and see, even if it’s a laptop or a desktop, there on that device is a fan somewhere that’s pulling air in, and it should be exiting out another part of the case.

You’ll probably want to look in a desktop computer especially, because the layout of the motherboard becomes very important, especially the cables that you use to connect hard drives, cables that you’re using to connect back to the case itself all have an effect of the air flow through the device.

So you want to be sure that all of the fans are able to pull air through as efficiently as possible, and that none of those wires or cables are getting in the way. There’s a lot of different styles of fans, and a lot of different volume levels of fans that you can have in your case. You may not just have one.

You may have multiple fans, and they may be different sizes, but they all work together to make sure that you’re able to take the cool air from the outside and blow it through the inside of the computer to cool it off. Here’s an example of a server appliance that is using that same idea. There are fans that are pulling from the cool side and pulling that on top of and through the motherboard, and the air is exiting out these holes in the back.

And that’s an important consideration, is you want to be sure that those holes are always clear. You want to be sure there’s no dust. You want to be sure that the air is able to come into the computer and exit out as quickly as possible. If these start to get plugged, you’ll find that the temperature inside of your computer will rise very, very rapidly.

If you’re adding a fan or replacing a fan and a motherboard, you’ll find there are very standard sizes, usually something like an 80 millimeter or 120 millimeter, or different types, depending on the case that you have. These fans can also run at different speeds. Often you can plug the fan into an interface, and the motherboard sensors will determine how fast that fan needs to run based on how hot the inside of the computer case happens to be.

There are also different noise levels. So if you don’t like the fan that’s inside of your desktop computer now, you can probably find one that is much quieter at exactly the same size, that probably moves the same amount of air, and replace it, and immediately have a quieter computer. But we don’t always have to use air for our computing. We could use liquid. And these days, the liquid is a coolant that we are circulating.

In this case, you can see circulating from a connection that’s right on top of a processor, and it’s moving into a fan. It’s radiating out that heat as the air passes through, and then the liquid goes back onto that particular area to get heated up again, and the process repeats. It’s the same process we use for automobiles. It’s the same process we use for our large mainframe computers.

We’ve taken that liquid cooling and collapsed it into a size that’s small enough to put inside of our desktop computers. You usually see this on high end systems. If you’re doing a lot of gaming or a set of processes that really increases the amount of work the CPU does, maybe you need some additional cooling that the air cooling is just not going to be able to do for you.

And if you’re experimenting with your computer and you’re overclocking the CPU itself, you know that that processor is going to get warm. That may be a perfect example to, instead of using air cooling, use some type of liquid cooling for your processors.