CPU is the most important part of a computer and that’s why it is essential for the CPU to stay cool for performing at its best. It is natural for a CPU/processor to heat up when you are using it for a long duration. To keep it cool all the time, we use a heat sink on top of the CPU. The heat from the processor is transferred to the heat sink and the heat sink with its huge surface area and cooling fans will dissipate the heat away. To aid the heat transfer between the CPU (or the IHS of the CPU) and the heat sink, we use a special compound known as thermal paste. Over time, this thermal paste will become dry and loses its thermal conductivity. So, we have to remove the existing thermal paste from the CPU and apply new paste. But how to clean thermal paste off CPU?
If you are new to the concept of cleaning and applying thermal paste, then this guide is just for you. Here, we see a step-by-step process on how to remove/clean thermal paste off a CPU and also apply fresh paste. We will start with gathering the things/tools that are necessary for the process, preparing your computer, and then cleaning the thermal paste.
Importance of Thermal Paste
Before understanding the need to remove old thermal paste, we will take a quick look at what exactly is the need for thermal paste in the first place.
We said earlier that heat sink helps extracting the heat from CPU and dissipating it away. Can’t we directly seat the heat sink on top of the CPU? For the naked eye, the surfaces of the CPU’s IHS (Integrated Heat Spreader, the metal part on top of the actual CPU) and the heat sink looks completely flat. But if you look at them under a microscope, then you can see that the surfaces aren’t flat and they have ridges and valleys.
Do these imperfections have an impact on the transfer of heat? When we are talking about of hundreds of watts of heat from a tiny surface of a CPU, then yes, they do. Air enters these tiny gaps and we know that air is not a great conductor of heat. As a result, heat transfer between the CPU and the heat sink won’t be perfect. This is where thermal paste comes into play.
Thermal Paste (also known as Thermal Compound or Thermal Grease) is a compound that helps in filling the microscopic gaps between the CPU and heat sink for a better thermal conduction.
Why Do You Need to Clean Old Thermal Paste?
As we use our computers, the thermal paste becomes dry over time. This is an issue as hard and dry thermal compound creates the same problem that a fresh thermal paste is designed to eliminate; it reduces thermal conductivity and the CPU might lose its performance due to heat. Hence, we have to clean off the dry thermal paste and apply fresh one.
If you are noticing an increase in CPU temperatures than normal, the thermal paste may or may not be a problem but it is definitely worth getting a clean-up and refresh.
Another reason why we need to clean old thermal paste is if you are upgrading the heat sink or the CPU Cooler. Whether you are getting a new and efficient air cooler or upgrading to water cooling (using an AIO Liquid Cooler), the first step is to properly clean and remove the old thermal compound off the CPU.
If you are thinking of adding new thermal paste on top of the old one (without removing or cleaning it), then please don’t. The thermal conductivity of any thermal compound degrades overtime. Even if you apply new thermal paste on top of the old one, you won’t be able to improve the overall thermal efficiency as the old one is still in contact with the CPU (or the heat sink) and the new one cannot magically penetrate and reach the surface.
How to Clean Thermal Paste Off CPU?
1. Prepare the System
The first step is to shut down the computer and turn it off completely. To be on a safe side, you can unplug the power supply from the outlet. But before that, you can run your computer for a while (say 20 to 30 minutes) so that the thermal paste isn’t completely dry (which will make things hard while removing the CPU Cooler).
Additionally, take necessary ESD (electrostatic discharge) precautions while working with CPU and other sensitive (and expensive) components.
2. Gather the Tools
While this is happening, you can gather all the necessary tools that you will need to properly clean the thermal paste.
- Isopropyl Alcohol (IPA): With 90% or higher alcohol content. Main component that cleans the thermal paste without any effect on the electrical components.
- Lint-free Cloth: Usually a good quality microfiber cloth will be sufficient. This helps cleaning the thermal paste after diluting it with alcohol.
- Cotton Swabs or Cotton Balls: A good tool for applying alcohol on the surface as well as cleaning the thermal paste.
- Kitchen Towels: Another useful tool for cleaning thermal paste off a CPU or heat sink. Alternatively, you can also use new coffee filters as well.
- New Thermal Paste: Once we clean and remove the old thermal paste, we have to apply new compound. Get a high-quality thermal compound from reputable manufacturers such as the Arctic MX-4.
- Other Things: Screwdriver (to open the side panel of the computer case), Plastic Scraper (to remove stubborn thermal paste), Latex Gloves (to protect your hand/fingers as well as sensitive components on motherboard), Soft-bristled Cleaning Brush (to clean any dust), Anti-static Wrist Band (to protect sensitive components from ESD).
3. Open the Side Panel
It is now time to open the side panel of the case. Depending on your case, this can be as simple as turning some thumb screws or using a screwdriver to unscrew the screws. This will give you access to the motherboard inside case.
If the job is simply cleaning the old thermal paste, then you don’t need to remove or disconnect anything else.
4. Remove the CPU Cooler
The next important step is to remove the CPU Cooler from the CPU. Again, this step depends on your setup and the type of CPU Cooler you have. For normal air cooler, all you have to do is loosen some screws or twist some tabs. In case of a water cooler, you have to remove the water block from the CPU. Irrespective of the type of CPU cooler, be gently while taking the cooler out. Do not pull the cooler with excessive force but rather try to twist it back and forth.
With this step, we will have access to the CPU surface as well as the surface of the heat sink. Some authors recommend taking the CPU out of the motherboard but some don’t. Our suggestion is to keep the CPU in its socket in the motherboard. This way, you won’t accidentally come in contact with the highly sensitive pins on the motherboard or the pads on the CPU. If you have an AM4 AMD CPU, then the CPU has the pins. Taking the CPU out of the motherboard socket will expose these pins and the risk of damage becomes high.
5. Clean the Thermal Paste off CPU
This is the main step. Wear gloves and make sure that you don’t get the thermal paste on your clothes as it will be very difficult to wash it off.
Take the lint-free (microfiber) cloth and wet it with isopropyl alcohol. Gently start wiping the surface of the CPU in a circular motion with this wet cloth from the edges towards the centre. This way, we can avoid sending the old thermal paste anywhere else on the motherboard. Don’t apply too much pressure or scrub. The isopropyl alcohol will help you in this regard.
You can use cotton swabs or cotton balls dipped in isopropyl alcohol for cleaning as well. After initial cleaning with cotton swabs, you can finish the job with a microfibre cloth.
In case the old thermal paste is very stubborn, then we can scrape it with a plastic scraping tool. Only remove the top part of the thermal paste using this method (scoop from the edges, inwards to the centre). For deep cleaning, we have to use a microfibre cloth or a kitchen towel (or even a coffee filter).
6. Clean the Thermal Paste off CPU Cooler
Repeat the same process and clean the thermal paste off the CPU Cooler. Clean the edges and other areas that might have residue of the thermal paste.
7. Dry the CPU and CPU Cooler
After removing and cleaning the old thermal paste off CPU and CPU Cooler, we can perform a final clean by using a fresh piece of lint-free cloth with isopropyl alcohol and cleaning any leftover grease or residue. Do this for both the CPU and the CPU Cooler.
There are special thermal paste remover solutions that you can use instead of isopropyl alcohol.
After this, let the CPU and the CPU Cooler dry (for at least 30-minutes to 1-hour). In case you went with the thermal paste remover, then it will have separate instruction on how long to wait before it completely dries off.
8. Apply New Thermal Paste
Next step is to apply new thermal paste to the CPU. Keep in mind that we don’t have to apply new thermal paste to the CPU Cooler. The simplest way to apply thermal paste is to place a “pea-sized” amount of thermal paste from the syringe it comes it right in the centre of the CPU. But depending on the type of your CPU and requirements, there are several patterns of applying thermal paste.
9. Install the CPU Cooler
The last step is to install the CPU Cooler back on the CPU. Apply even pressure while dropping the CPU cooler on top of the CPU without any wiggly actions. Tighten the screws of the cooler in appropriate order and we are ready to conduct a performance test.
10. Test Your PC
The best way to check if your new thermal paste is working or not is to use your PC normally but monitor the CPU temperatures.
The Ultimate Thermal Paste Alternative
When you clean the thermal paste off the CPU sockets, you will understand that it is really sticky and messy. The after-cleaning can be a nightmare. That is why there are many who search for an alternative to the thermal paste, and fortunately, there is one such alternative available.
The alternative is Innovation Cooling Graphite Thermal Pad. You need to place such a pad in between the socket and the heat sink, just like thermal paste. As a matter of fact, these thermal pads offer better heat conductivity than thermal paste. There is no need for cleaning them as such, and you can even replace them if there is a need. It is about time that manufacturers start using them.
Frequently Asked Questions
How often should you apply thermal paste?
Answer: Depending on your usage and the quality of the existing thermal paste, you might have to re-apply thermal paste every 2 to 3 years. If you notice an increase in CPU temperature (higher than normal), then it is advisable to clean and remove thermal paste from CPU and apply fresh one.
What can be used to remove old thermal paste?
Answer: 90% or more Isopropyl Alcohol is the best solution to clean old thermal paste. More % of alcohol is always better (as it contains less % of water which is important when using with electronics). Alternative solutions include rubbing alcohol (again preferably with isopropyl alcohol rather than ethanol). There are also special thermal paste cleaner solutions with sole purpose of cleaning old thermal compounds.
Can I use paper towels to clean thermal paste?
Answer: Lint-free microfibre cloth is the ideal material to clean thermal paste. Alternatively, we can use good-quality kitchen towels (paper towels), cotton swabs (or cotton balls), or even coffee filters. If you use material that might leave lint (paper towels, cotton swabs, or coffee filter), then you have to finish the cleaning with a microfibre cloth.
Can I clean thermal paste with compressed air?
Answer: No. You cannot clean thermal paste with compressed air. We generally use compressed air to clean dust and debris from computer fans, motherboard, etc. To remove thermal paste, we have to use a microfibre cloth dipped in isopropyl alcohol.
Should I let the CPU dry after cleaning?
Answer: Yes. You should dry the CPU. You can wait for the CPU to dry naturally (might take some time) or use a dry microfibre to suck all the moisture from its surface.
Do I need to clean the heatsink as well?
Answer: Yes. Whenever we remove the old thermal paste from a CPU, we also need to clean the thermal compound from the surface of the heat sink as well. This way, when you apply fresh thermal paste on the CPU, the old (and dry) thermal paste on the heat sink will not interfere with the heat transfer.
Conclusion
Thermal paste is a necessity for the cooling of the CPU or processor. Cleaning them is equally necessary as it dries off with time. You can be sure that the thermal paste cleaner and the surface purifier are not going to damage any electronic part. Be gentle while cleaning, and do not rush. Give enough time for drying and think about using a cooling thermal pad instead of a thermal paste.
