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How Long Does Thermal Paste Last And Other Questions Answered

If you own a gaming PC, one of the most important things that you need to know is computer maintenance and cleaning. We’d like to think that our gaming PC’s are invincible because they’re made from high-end parts, but sometimes, things can go so wrong at one point and you’ll need to do maintenance sooner than later.

In this article, we’ll be discussing one of the most important components of computer maintenance: thermal paste. We’ll know what this item is about, how long does thermal paste last, and when you should be replacing it.

What Is Thermal Paste?

Thermal paste, or thermal compound or thermal grease to some, is a substance that’s applied between the heat sink and processor. These are available in small tubes at electronic stores, along with a small shovel-like tool to help you apply the paste.

A tube of new thermal paste is what you initially need when you’re building a PC the first time. Most of the time, the CPU heat sink already has a pre-applied thermal paste so you can just install immediately. But the hardcore PC builders will manually reapply thermal paste because they already have a brand preference.

Thermal pastes do one thing and that’s to help keep the CPU cool by transferring heat into the heat sink. The heat sink is then responsible for expelling heat away from the CPU, allowing your CPU to stay cool at all times (when possible).

How Does Thermal Paste Work?

CPUs generate a lot of heat when they’re working on heavy tasks, such as rendering or gaming. Your case fans or PC fans may keep other parts of your system cool, but not for the CPU. You see, air is a bad heat conductor. You want to minimize the distribution of air between CPU and heat sink.

The heat sink is pressed tightly into the CPU, which prevents air from getting into the CPU but this isn’t a complete seal. To really prevent air from getting into the processor, you need to seal the tiny gaps between the CPU and heat sink.

The thermal paste will allow you to completely seal the surface of the CPU and the heat sink’s contact point. The paste will cover the hardware’s surface grooves and small gaps, allowing for a complete seal and improving heat transfer rate.

Thermal pastes don’t last forever, unfortunately, so you’ll need to replace them over time. A dried out thermal paste has reduced effectiveness, so your CPU may become hotter than normal. When this happens, you’ll need to replace thermal paste before you damage the CPU.

How Is Thermal Paste Applied?

The debate on how to use thermal paste is intense, specifically on how to apply thermal paste. You’ll find a lot of videos, articles, and theories on the right way to apply thermal paste. It’s just difficult to pinpoint which one’s the right one.

But the simplest way to apply thermal paste is as follows:

Pea Sized Amount How Long Does Thermal Paste Last
  1. Apply a pea-sized drop in the middle of the CPU.
  2. Attach the heat sink into the processor.
  3. Apply pressure on all four corners of the heat sink, ensuring that the thermal paste is distributed across the surface evenly. If your thermal paste has an applicator, you can use this to distribute the paste evenly before you clamp down the heat sink.
Spreading Thermal Paste How Long Does Thermal Paste Last

Now there are different ways to apply thermal pastes on CPUs, so regardless of what method you pick, you have to make sure that there are no gaps or bubbles on the CPU and heat sink’s surface. Otherwise, heat transfer and distribution will be affected.

Where Should People Store Thermal Pastes?

Thermal pastes are best stored in cool areas. People would suggest storing it in a freezer but this is a bad idea. There is a risk that the thermal paste might damage your CPU after you freeze it.

If you have leftover thermal paste, you can store it inside any airtight container, like a Ziploc bag. You’ll want to avoid placing this container under direct sunlight or heat.

For people in tropical countries, you’ll have a higher than normal room temperature. The best way to store thermal paste is to store it in a drawer in an air-conditioned room to prevent it from drying too fast.

But from experience, thermal paste is super affordable so you can just throw the old thermal paste as soon as you’re done with it. If you want to replace thermal paste, it’s often best to purchase a new one than to reuse old thermal paste.

How Long Does Thermal Paste Last?

Most experts don’t recommend reusing leftover thermal paste. Old thermal pastes can dry out a bit even if stored properly. If a thermal paste is a bit dried out, it may end up damaging your CPU or heat sink.

There’s also the mixture of certain thermal pastes that need to be considered when storing or reusing them. Some brands might last longer because their paste’s formula are unique. Thermal pastes also have different measurements, one of which is the Watts per meter-Kelvin or w/mK. This is how the rate of heat transfer in a homogenous material is transferred. The higher the w/mK, the better thermal conductivity.

Thermal conductivity determines how fast heat transfer is, either from receiving it from a hot material or dissipating heat towards a colder material.

So, how long does thermal paste last? It varies depending on the brand, but the general average is a couple of years.

When Is Thermal Paste Replaced?

There are certain situations that will determine when you should replace thermal paste.

Replacing Thermal Paste How Long Does Thermal Paste Last

First, when you remove the heat sink from the CPU. If you see some of the thermal paste is on the heat sink and some on the CPU, this is a sign that you should replace the thermal paste. Replacing the heat sink back into the CPU will leave you with air bubbles and gaps, significantly affecting temperature regulation.

In this situation, you should clean both the surfaces of the CPU and heat sink with alcohol before applying a new one. You also need to get rid of old thermal pastes as you don’t want to mix a new tube with an old one.

Another situation that calls for replacing thermal paste is routine maintenance, which is once every two or three years. Not all thermal pastes have the same level of efficacy though. Thermal paste degrades over time, which affects the performance of your system unit.

If you recently bought a PC, the best time to replace the thermal paste is two years after. It’s best to assume that the longevity of the stock thermal paste used is about two years. Then once you go for a newer thermal paste, go for the brand that offers a longer life span, usually about three years onwards.

Is It Possible To Use Too Much Thermal Paste?

The answer is Yes. Ideally, you only want to use a pea-sized amount on the CPU before distributing it evenly.

Too Much Thermal Paste How Long Does Thermal Paste Last

You’ll know you used too much thermal paste when the paste oozes over the CPU and heat sink’s corners. You know how peanut butter or jelly would flow into the corners when you squeeze both sides of the bread together? It’s a similar situation for thermal pastes.

When you use too much thermal compound, you might end up damaging your components. At the very least, the thermal compound won’t do a good job when it comes to insulating heat.

Wrap Up

Thermal paste helps with managing and dissipating heat away from the CPU, on top of using a CPU cooler. This liquid metal compound prevents your CPU from becoming extremely hot. When a CPU becomes too hot, system performance is affected. So the number of cores it runs on is reduced up until the temperature is regulated.

Thermal paste does affect temperature regulation as it transfers heat away from the CPU and into the heat sink, which expels the heat away from the system.

How long does thermal paste last? Thermal paste lasts for about a couple of years on a newly installed CPU. The longevity of thermal pastes vary depending on the brand, ingredients, and measurements. When you’re replacing a new thermal paste, go for different manufacturers that have longer life spans, usually three years and above.

Leftover and used thermal paste tubes should just be disposed of because there’s no point in reusing old stock. Thermal pastes are affordable and easy to find, so you don’t have to worry about saving up an old tube.

James Stephenson

james stephenson profile picJames is a gaming and tech enthusiast. He has been playing computer games since the Commodore 64 days in the 80s. He has worked as a Broadcast Engineer with BBC News and knows a thing or two about building, fixing, and playing with PCs.