Do We Use the Whole Tube of Thermal Paste on a Processor?

“How much thermal paste should I apply?” — it’s a common question asked by many rookie computer owners. Finding out the right amount of thermal paste has been a dilemma for most people.

The latest alteration of this ancient question is related to thermal paste tubes. Are thermal paste tubes intended for one-time usage? Should you go ahead and apply the entire tube to your CPU or GPU?

If that sounds like something you’ve been wondering about, this post is a must-read for you. Keep reading to learn everything on the matter.

How much thermal paste should you use?

Well, there’s no one-size-fits-all amount that we can recommend. It all depends on the size of your CPU, i.e., its length and width.

You see, to get maximum thermal performance, you need to apply a thin, but even layer of the thermal paste between the CPU/GPU and the heatsink. If you have a bigger CPU, it will naturally take more thermal paste to form that uniform layer. On the other hand, if you have a smaller CPU, it will take a lesser amount of thermal paste to form that layer.

Under ideal conditions, 0.2ml is the perfect amount for a 30mm by 30mm CPU — which is, of course, the most common size of CPUs out there.

If you’d like to find out the right amount of thermal paste for your specific use case, Kooling Monster Thermal Paste Calculator is at your service. It’s an easy-to-use tool that you can use to calculate the exact amount that would be ideal for your CPU size.

To use the calculator, simply drag the sliders till you’ve got an accurate measure of your CPU’s length and width. If you don’t know the length and width, refer to your CPU’s packaging or product page — you will find it there.

If you’re using Kooling Monster KOLD-01, all you’d need to input is the CPU specifications and the size of your tube. But if you’ve got some other thermal paste brand, you’d also need to input the density of the paste. Again, if you don’t know the density, you can find that out on the packaging of the paste or its product page.

What happens if you use the entire tube of thermal paste?

In most cases, your tube will have more thermal paste than you need to apply in a single go. So, no matter where you’ve purchased your tube from, refrain from putting on all the thermal paste in the tube at once.

Even if your thermal paste tube came in with the CPU/GPU itself, it should still be more than what you need to apply in one instance.

Normally, CPU sizes range from 30mm by 30mm to 60mm by 60mm — and in this range, you will never need more than 0.6ml thermal paste. In fact, as mentioned earlier, 0.2ml is the ideal amount for a 30mm by 30mm CPU size.

GPUs are mostly even smaller than CPUs. So, you won’t need more than 0.6ml for GPUs, either.

Learn more about Kooling Monster’s in-house case study on the thermal performance of different thermal paste amounts.

The amount of thermal paste you get per tube depends on the brand you pick. Plus, each brand might make more than one tube size, so there’s no universal way to find out how much of a tube you need to apply.

The best way to go about the situation is to find out your thermal paste tube size, and use Kooling Monster Thermal Paste Calculator to figure out how much of the tube you need to apply. If you didn’t notice already, the calculator shows you the amount you need to apply in 3 different metrics, i.e., by volume, by weight, and by tubes.

How to choose the right size of thermal paste tube?

Many thermal paste brands come with a weight label, however, that’s not the specification you need to look for.

First and foremost, you must find out the volume of your thermal paste — as that’s the easiest metric to work with. However, if the specifications don’t mention volume, you’d need to calculate it yourself. Luckily, there’s a really easy formula you can use for that.

If a tube doesn’t mention the volume, it most probably mentions the weight in grams and the density. To find out the volume, all you need to do is divide the weight by density. Note that some brands may use the term “specific gravity” in place of density.

For example, KOLD-01 has a density of 2.6 and a weight of 1.8g. Divide the weight by density and you get the volume of the tube, 0.7ml. And you guessed it, 0.7ml is more than you will ever need in the case of most CPU sizes.

What happens if I apply too much or too little thermal paste?

Putting too much or too little thermal paste diminishes the thermal performance.

If you put too much of it, the thermal paste layer would become too thick, which increases the physical distance between the heat sink and the CPU/GPU. When that happens, heat transferability is affected drastically. If you put too little of it, an even layer of the thermal paste can’t be formed. Air gaps might be left in between, which again, decreases the thermal performance.

For optimum performance, you want a layer that’s not too thin or too thick.

The best way to go about the situation is to use our calculator to find out the perfect amount of thermal paste, then use your preferred application method to apply the right amount.

Learn more about what happens if you apply too much thermal paste to a CPU.

The bottom line

Under most circumstances, a tube contains more thermal paste than you would need to apply in a single go. So, you should never apply all of a tube in a single instance.

The rule of thumb is to use our calculator to find the perfect amount for your CPU size, read your tube’s specifications, and then apply the right amount precisely. If you can’t get the amount right, you could use the buttered toast application method to form a thin, even layer of thermal paste on your CPU.