Thermal paste, also known as thermal compound or thermal grease, is a conductive material that is used to improve the thermal contact between a CPU and its cooler. When applied correctly, the thermal paste can help to lower temperatures and improve the performance and stability of a computer.
But is thermal paste necessary for every CPU?
Although some CPUs may not require thermal paste, most of them will benefit from its use. Also, it has been shown that thermal paste lowers CPU temperature and improves performance.
In this article, we will dive into the reasons why thermal paste is important and provide some guidelines for applying it to your CPU.
In this article, we will dive into the reasons why thermal paste is important and discuss some of the potential consequences of not using thermal paste. We will also address some common misconceptions about its use. Whether you are building a new system or simply replacing a CPU cooler, this article will provide the information you need to make an informed decision about using thermal paste.
Let’s dive right in!
Here’s why CPUs need thermal paste
We know that the CPU is the brain of a computer, responsible for executing instructions and performing various tasks.
The processor generates a lot of heat as it works, and if this heat is not properly dissipated, it can cause the CPU to malfunction or even fail. This is where thermal paste comes in. Thermal paste is a thermal compound used to fill the small gaps between the heat sink and the CPU.
It is a thin, gooey substance that is applied to the surface of the CPU before the heat sink is installed. The purpose of thermal paste is to improve the heat transfer between the CPU and the heat sink, helping to dissipate heat more efficiently.
One of the key properties of thermal paste is its high thermal conductivity. This means that it can conduct heat well, making it an effective material for transferring heat from the CPU to the heat sink. Thermal paste is also able to fill in the small gaps between the heat sink and the CPU, improving the contact between the two and further increasing the efficiency of heat transfer.
In addition to its high thermal conductivity, the thermal paste also has a low thermal resistance. This means that it has a low resistance to heat flow, which helps to reduce the amount of heat that is retained by the CPU. By dissipating heat more efficiently, thermal paste helps keep the CPU running at a cooler temperature, improving its performance and extending its lifespan.
Some thermal pastes are made with a variety of materials, including metal oxides, ceramics, and silicone, and it is typically a good idea to choose one that is known for its high thermal conductivity and low thermal resistance.
In theory, if a perfect cooler makes optimal contact in the precise region where heat is created, if it’s suitably flat and has sufficient mounting pressure, the benefit of thermal paste is limited because if there are no imperfections, you don’t need something to cover up imperfections.
In reality, there is no such thing as a perfect cooler. And, in particular, low-cost coolers. Especially for laptop coolers, where there is no competition between different cooler alternatives.
Because coolers have flaws, it’s useful to have a very simple, very cheap, very practical tiny aid that mitigates some of those flaws and enhances heat transfer.
Here’s the deal with the thermal paste: Thermal paste has no drawbacks.
If you have a laptop and wonder the same thing, we highly recommend reading Do Laptops Need Thermal Paste? Yes, Here Is Why
What EXACTLY happens when you don’t add thermal paste?
Because of the microscopic gaps between the processor and the heat sink, the two surfaces do not make full contact with one another, leaving a pocket of air between them. Because air is a poor heat conductor, the effective contact area is diminished, and small air pockets are sufficient to keep your cooler from performing successfully.
The temperature difference between mid-range and high-quality air coolers is about 3-8°C. The temperature differential between high-quality water blocks and inexpensive unbranded ones can be as much as 10°C. Thermal compounds are roughly the same.
Temperature fluctuations might range from 1 to 10°C depending on the quality. That is, simply by selecting the correct thermal compound, you can get huge temperature decreases.
Does thermal paste improve performance?
The thermal paste helps to transfer heat from the CPU to the heatsink, which helps to keep the CPU cool. If the CPU runs too hot, it can throttle its performance to prevent overheating, leading to lower performance.
By using a thermal paste to improve the heat transfer from the processor to the heatsink, you can help the CPU to run cooler, which improves its performance.
However, it is crucial to note that in some cases, the performance difference will be small, while in others huge. The main benefit of using the thermal paste is ensuring that the CPU is properly cooled to prevent overheating and damage. Additionally, other factors, such as the CPU itself, the motherboard, and the overall system configuration, can significantly impact performance.
ALKtech did a great job of comparing CPU performance with and without thermal paste in Cinebench R23, DaVinci Resolve R17 and Far Cry 5. Here are the results:
| IDLE Temperatures | With Thermal Paste | Without Thermal Paste |
| Temperature Range | 57°C-60°C | 57°C-60°C |
| CINEBENCH R23 | ||
| Multi Score | 8454 | 8218 |
| Average Temperature | 93°C | 94°C |
| DAVINCI RESOLVE R17 | ||
| Render Time | 3m29s | 3m36 |
| Average Temperature | 91°C | 93°C |
| Far Cry 5 | ||
| Average FPS | 63 | 63 |
| Average Temperature | 78°C | 80°C |
*CPU: AMD Ryzen 5 3600
During my research, I stumbled upon another great test. Here are the results:
| 30 Min Average °C With Paste | 30 Min Average°C Without Paste | |
| IDLE Temp (50% Fan Speed) | 22.8°C | 28°C |
| 100% CPU Usage (50% Fan Speed) | 56.6°C | 93.9°C |
*CPU: Intel 9700KF
Here is another great test in which the guy compared CPU performance with and without thermal paste.
CPU: Ryzen 7 3700X
Thermal paste: Arctic MX-4
| Average °C With Paste | Average°C Without Paste | |
| IDLE Temp (10m) | 33°C | 35°C |
| Rocket League (15m) | 51°C | 55°C |
| Cinebench R23 (5m) | 73°C | 82°C |
As we can see, applying thermal paste improves CPU performance by lowering its temperature. This is true for IDLE and intensive tasks, such as gaming.
How long can a CPU run without thermal paste?
First things first, it is not recommended to run a CPU without thermal paste, as it is an essential component in helping to dissipate heat from the CPU to the heat sink. Without thermal paste, the CPU will quickly overheat and can be damaged.
Even if the CPU is able to run for some period without thermal paste, it is not a good idea to do so, as it will significantly reduce the lifespan of the CPU. It is essential to use a sufficient amount of thermal paste when installing a CPU to ensure that it is able to run at its optimal temperature.
It is hard to say how long a CPU will run without thermal paste. However, we know that some processors won’t run at all, while others can run for days, months, or even years. It all depends on the cooler and the CPU itself.
Does replacing thermal paste help the CPU?
This is a great question. In theory, replacing thermal paste may help the CPU if it is not properly applied. However, if you did the application properly, replacing thermal paste will probably not do very much.
Now let’s see what the real-world experience says. In this video, the guy tested a 7-year-old thermal paste with the new one. Here are the results:
| 7-Year-Old Paste Average °C | New Paste Average°C | |
| IDLE Temp | 37-41°C | 37-42°C |
| Full load | 57-62°C | 56-64°C |
As you can see, there is no practical difference. However, if you notice some temperature issues over time, try replacing it and see the results.
Do coolers come with thermal paste?
Some CPU coolers come with thermal paste pre-applied to the base, while others do not. It is always crucial to check the documentation for the cooler to see whether it includes thermal paste or if you will need to purchase it separately.
If the cooler does not come with thermal paste, you will need to purchase some and apply it yourself when installing the cooler. There are numerous different types of thermal paste available, and it is generally a good idea to choose one that is specifically made for use with CPUs. It is also important to use a sufficient amount of thermal paste to ensure that the CPU is able to run at its optimal temperature.
Conclusion
From the tests we were able to analyze and from numerous other people’s experiences, we can confidently recommend using thermal paste.
“But it is not as crucial as people may think. There is no significant improvement in performance!”
Even if your CPU does not get damaged over time (which I highly doubt) without thermal paste, we will still recommend using it for a very simple reason: it costs only a few bucks and it lowers CPU temperature at least by a few degrees.