Does Thermal Paste Smell?

Building a PC is an expensive and time-consuming task and many undertaking the task for the very first time don’t know what to expect (or what to look out for) when it comes to buying and assembling all of the components needed in the build. This can include thermal paste.

So, what can you expect when you first use thermal paste? Will thermal paste smell, and more importantly, what does a distinct chemical smell from thermal paste mean?

Does Thermal Paste Smell?

Not all thermal pastes are the same. Some are thinner, some are more fluid, and some are odorless. It will vary between pastes and manufacturers.

Sometimes thermal paste can smell, and this can be an indicator of the ingredients and method used to create this important element of your cooling system.

As with any other type of paste or gel, smells, textures and consistencies will vary between brands. Different manufacturers will use different organic solvents and this can cause stronger more chemically smells.

What Causes Thermal Paste To Smell?

If there is a clear smell from your thermal paste, then this is a sign that your chosen thermal paste is emitting chemicals into your environment. It’s safe to assume that the stronger the smell, the stronger the chemicals. Of course, not all thermal pastes will emit an odor so it’s something to consider when you’re weighing up your options and choosing which paste to buy.

Applying a thermal paste is all about improving heat conduction between the CPU and heatsink, therefore manufacturers of pastes will add metal oxides in an attempt to make the paste more effective and boost the formula's thermal conductivity.

Whilst metal oxides do provide good conductivity, there is a balance to be achieved. Ignoring other necessary properties can make a paste less conductive. The most effective pastes will be developed with this balance in mind.

For a thermal paste to be effective it must not only be highly thermally conductive, but it must also be easy to spread. A thinner layer will mean improved heat transfer, it’s therefore also important that a paste is incredibly fluid and spreadable. (Learn more about What Is Thermal Conductivity and Is It Always Good for Thermal Paste?)

Many manufacturers use organic solvents to increase fluidity where there are too many metal oxides. Typically these organic solvents are responsible for the chemical smell that comes from the paste.

Of course, chemical smells in the air are usually a bad sign. Not only are they bad for the environment but they can be bad for you if you are exposed to these chemicals for prolonged periods of time.

There are several market options for chemical vapor-free formulas, like the popular KOLD-01 thermal paste that uses a special formulant rather than an organic solvent to ensure both conductivity and fluidity of the paste.

Thermal Paste Smell After Application

If your thermal paste does have a chemical smell, then this will likely get stronger when it is spread on the CPU.

The method you use to apply the thermal paste won’t impact the intensity of this smell too much. It is due to the paste’s exposure to air, meaning more solvent is exposed and therefore the smell is stronger.

Why Does My Thermal Paste Smell Burnt?

If you smell burning from your system, then it’s usually a sign that something is malfunctioning or overheating. It could be a sign that it’s time to change your thermal paste.

Many people forget about this small element of maintaining a PC but operating with dried thermal paste can cause a number of problems.

After some time, thermal pastes, even high-quality ones, will need to be removed and reapplied. Leaving it for too long can mean that your system does not properly regulate its temperature and you will likely see performance suffer and may even experience damage to your hardware. (Learn more about How Often Should You Replace Thermal Paste?)

The time needed between maintenance will depend on the quality of paste you’ve used, the intensity of activity on your system, and the general temperature in the environment housing the PC. It can range from anywhere between a couple of months to a couple of years. It is always best to check regularly to ensure your system does not suffer from missed replacements.

If your system seems too warm or slow, it's time to take a look at your thermal paste. Look out for it being dry or cracked in appearance or it looking thicker than when it was applied. These are all signs that your thermal paste is due a change.

If you notice this changed appearance, get hold of a thermal paste removal kit and a new tube of paste. You can follow our step-by-step guide for more details on the process.

Choosing High-Quality Thermal Pastes

Choosing a high-quality thermal paste comes down to two key things. It’s fluidity so that it’s easy to spread, and its conductivity.

It’s fairly easy to find a high-quality thermal paste that is both conductive and fluid, but you may also want to consider its ingredients and the effect potential solvents can have on the environment. Vapor-free formulas are easily available and popular choices that incorporate all of the right qualities without emitting too many chemical smells as you are building your PC.

We recommend KOLD-01, vapor-free thermal paste.