The Role of Thermal Paste in Your PC

If at any point you’ve taken apart a computer or have seen a CPU built from the ground up, you may have noticed a gray or silver substance applied in between the CPU and the cooler. That material is thermal paste, which, although may look unimportant, has a large role to play in the smooth running of your PC. It is the element that remains in the background of the build and yet is a very important element for the performance and longevity of your computer.

Let’s go over what thermal paste is, why we can’t live without it, how it functions, and how ignoring it may cause your PC issues.

What Exactly Is Thermal Paste?

Thermal paste, a term that also includes thermal compound and thermal grease, is a kind of heat-conductive material used in between two surfaces, which is mostly the CPU or GPU and the heatsink or cooler. In today’s world of very powerful processors, which generate large amounts of heat during operation, the role of the cooler is to take that heat out and dissipate it, in turn keeping the processor at a safe working temperature.

Even so, the metal of the CPU and cooler may appear smooth to the naked eye. At a microscopic level, these surfaces are full of very small defects and gaps. In these gaps, air gets trapped, which, as a poor thermal conductor, does not do a good job of transferring the heat. Thermal paste is used to fill in these small defects and gaps, which in turn pushes out the air and creates a better path for the heat to travel from the processor to the cooler.

Why Heat Transfer Is So Critical

When a computer component like a CPU or GPU gets too hot, a few things play out. At best, we see the device slow down to cool itself off, which is a feature known as thermal throttling. At worst, it may suddenly die out or may sustain permanent damage. Heat is the enemy of a processor and something we must do our best to manage in order to maintain performance and have the hardware run at peak performance for as long as possible.

Even at the top of the cooling system range—liquid coolers, premium fans, large heatsinks—without properly applying thermal paste, all that is wasted. It’s as if you have a race car with deflated tires. All that power in the car will go to waste if you don’t have proper contact between the car and the track.

Different Types of Thermal Paste

Not all thermal pastes are the same. We have many types which differ in performance. Here are the main ones:

1. Metal based thermal pastes — we see these made of silver, aluminum, and other conductive metals. They do an excellent job at transferring heat but also may conduct electricity, which is something to be aware of during application to avoid short circuits.
2. Ceramic based thermal pastes — We see in these types of pastes the use of ceramic particles in a silicone base. They are a better choice in terms of safety as they do not conduct electricity, although in terms of thermal performance some of the metal-based options may outperform them.
3. Carbon based thermal paste — we see these as a great balance between what is safe and what performs. Carbon pastes do not conduct electricity and at the same time they do very well with heat transfer, which in turn makes them a favorite among PC builders.
4. Liquid metal — This is what enthusiasts and professionals use. Liquid metal pastes perform great in terms of heat transfer but also are highly thermally and electrically conductive. They also require extra care at application time and are not recommended for beginners.

Each different type has its proper use. For the average user and gamer, a ceramic or carbon-based paste will do just fine. For the power users who are taking their systems to the max, we see more into the metal-based or liquid metal solutions.

How to Apply Thermal Paste Correctly

Proper application of thermal paste is a must, which in turn is as important as which type of paste you put on. Not applying enough, which does not fill in the gaps enough, and applying too much, which in turn causes a mess or in some cases damage to components if the paste is conductive.

There are various application methods: The small dot, the line method, the spread-out method, and the X pattern. Of these, the small dot in the center of the CPU is the most common. As the cooler is pressed in, the paste goes out evenly.

Some coolers ship with pre-applied thermal paste. That is convenient and for the most part works great. But if you are building out your PC from scratch or in the process of upgrading parts, applying the thermal paste is an easy thing once you get the hang of it.

When Should You Replace Thermal Paste?

Thermal paste is not a one-time application and set-it-and-forget-it solution. Over time, it may dry out, crack, or become less effective, which in turn from constant on and off of the heat cycle causes it to do a poor job. This in turn causes your system to overheat.

As a rule of thumb, thermal paste should be reapplied every 2 to 3 years or at the time of removing the cooler from the CPU. Also, if you notice that your PC is running much hotter than it used to and you haven’t been putting in new paste recently, reapplying it may help to improve cooling performance.

Also, when you are upgrading your CPU or changing coolers, clean the old paste off with isopropyl alcohol and a lint-free cloth and then apply fresh paste.

Indications of Poor Quality Thermal Paste.

How do you tell if there is a problem with the thermal paste? Here are some signs of poor thermal paste:

• High CPU temperatures even at idle
• Thermal drop-off in performance during gaming or heavy use
• System goes down at high temperatures
• Fan spinning at high speeds constantly

If at these times issues present themselves and your cooling hardware is operating properly, the thermal paste may be the issue. It may have been applied incorrectly, has dried out, or was not the right type for your setup.

Thermal Paste and Overclocking

If you do extreme performance tuning of your CPU or GPU out of the factory settings, we’ve found that thermal paste plays a key role. Tuning them up results in greater heat production. Also, better thermal paste will be what makes or breaks whether your system remains cool and running or just dies on you.

Enthusiasts that run their systems at high performance levels frequently try out various thermal compounds to determine what works best with their build. In this case, each degree of cooling may translate to better performance or more room for overclocking.

A Little Bit Goes a Long Way.

In the PC build, thermal paste is a very cheap and small component which at the same time plays a large role in the system’s stability and performance. It isn’t flashy, it doesn’t light up, and it usually comes in a small syringe in the corner of a motherboard box. But to ignore it—or install it incorrectly—is to put the expensive components at risk.

Proper application of good thermal paste will keep your CPU cool and at optimal performance. It sees to it that your system does not slow down, crash, or, which is to say, die out from overheating. As you game, edit your videos, or just browse the web, the thermal paste is quietly in the background making all functions smooth.

Conclusion

Thermal paste is a behind-the-scenes hero in computers. It fills in the tiny spaces between your processor and its cooler, which in turn helps out with temp control. Though it may be easy to overlook, using the right kind of paste and applying it properly can greatly improve your PC’s thermal performance.

So when you build or put together that PC of yours, don’t leave out that small tube of gray goop. It may not be the most attractive thing in the kit, but it is a very important component which will keep your system cool, stable, and at peak performance.