Not many people even know what a thermal paste is because it’s usually discussed in pc building topics. You can rarely hear them being associated with laptops, and therefore the question of laptops needing thermal paste is valid for the average user.
Laptops need thermal paste in the same way a desktop PC does. Thermal paste connects the CPU or GPU chipset surface with a heatsink to extract the heat better, bringing the component to adequate operating temperatures. The CPU and GPU would overheat without thermal paste due to air gaps between them and the heatsink.
Let’s explain in a bit more detail.
What Is a Thermal Paste?
A thermal paste is a grease-like paste that allows heat transfer between two objects, in this case, two surfaces. When two surfaces are put in contact, their imperfections leave air gaps in between, and air doesn’t transfer heat very well.
When compressed, a thermal paste fills all the gaps and makes the heat transfer equal along the whole surface, allowing the heat sink to extract all the heat from the CPU or GPU.
A thermal paste is sometimes called CPU grease, thermal grease, thermal compound, thermal gel, or, more correctly, thermal interface material (TIM).
Is It Okay to Run a CPU or GPU Without Thermal Paste?
You can run low-end CPUs without thermal paste. It’s not suggested but is possible. Heat readings will be about 30-40% higher, and you will experience a freeze, or a restart, due to overheating if you try to run any game or other CPU-heavy program.
Any mid to high-end CPU won’t work without a thermal paste. The laptop will shut down as soon as you do anything to raise the CPU’s temperature. It will likely shut down even while booting Windows.
Any decent CPU generates enough heat to fry itself without cooling. Not having thermal paste is even worse because while a part of its surface could transfer the heat to a heat sink, the other part left with an air gap will get insulated and burn up even faster.
If you read closely through people’s claims about running CPUs without thermal paste, they are always talking about some extremely low-end, old CPU.
How Long Does Thermal Paste Last in a Laptop?
Five years seems to be a good consensus. However, it’s not a very accurate estimation. In reality, a thermal paste can last from one year up to ten or more years, depending on various conditions.
One of the major conditions affecting thermal paste longevity is how well it’s set up. If there are air gaps left in the middle, it will dry up much more quickly. The same goes for detaching a heat sink and installing it again without re-applying the new paste.
You might ask if thermal paste is supposed to dry up.
Most people say no, which is kind of true if we are talking about getting completely dry. However, it gets thicker and thicker in time, which in a way, is drying. It doesn’t really lose its heat transferring capabilities before it thickens so much that the contact surfaces come lose and form air gaps.
That can be especially problematic in laptops which are quite easy to flex. And yes, the motherboard flexes with the case, and so do all the components attached to it.
If you buy a pre-owned CPU used for CPU-heavy tasks, I would check the temperatures first, then clean and re-apply thermal paste if necessary.
Don’t try to fix it if it isn’t broken.
How to Know if a Thermal Paste Is Good?
The best advice anyone can give you is never to touch the cooler and heat sink unless you know there is a problem with it. Otherwise, you will have to re-apply thermal paste.
The best way to know if the thermal paste is good is to check the temperatures with free software like Open Hardware Monitor.
If the temperatures are fine, there’s absolutely nothing wrong with thermal paste.
If temperatures are too high, it’s either the problem with the thermal paste or the cooler/heat sink is too small for that processor.
What Happens With a Laptop if You Don’t Change Thermal Paste?
As mentioned before, your CPU will overheat and shut down if the paste drys and cracks, acting more like a thermal insulator than a conductor.
Slowly but surely, you may begin to hear or see signs of excessive fan noise or random computer crashes, which are signs of poor thermal management and ultimately lead to system failure.
When this happens, the CPU will overheat since the heat from the CPU to the cooling block isn’t being transmitted properly.
Damage to the CPU is inevitable if this occurs frequently.
CPUs have a feature known as thermal throttling that slows down the performance when temperatures rise too high over an extended time. However, within that time frame before the throttling activates, it can already be too hot and crash the system.
CPU idle temperatures typically range from 40 to 55 degrees Celsius (100 – 130°F), depending on the cooling system used and the type of laptop casing. You don’t want to observe temperatures above 60°C when idling or higher than 80°C under load.
That’s when you know you should’ve already changed the thermal paste.
Does Changing Thermal Paste Improve Performance?
Changing thermal paste can definitely improve performance, but not in every situation.
Changing the paste will affect performance tremendously if something is wrong with the paste. But what about situations when everything seems fine? Would it slightly improve the performance or not?
From my experience, older CPUs didn’t benefit from changing thermal paste prematurely. Newer high-end CPUs are a different story.
I’ve seen performance improvements even when re-applying thermal paste after six months of CPU-heavy use. More so in laptops than desktop PCs. While temperatures didn’t change much from the old days, the heat energy generated is much higher.
What Thermal Paste to Use in Laptop?
With thermal paste, you have two options; non-conductive and conductive.
Non-conductive thermal paste is a standard. Overall, it’s a great performing, cheaper, safe, and easy to use option. In my opinion, you should never look beyond non-conductive thermal paste unless you are into some hard-core mining rigs.
Some of the best performing brands include Arctic, Thermal Grizzly, and Corsair. My personal preference is Thermal Grizzly Kryonaut paste. The best performance out of all temperature-wise. However, it’s a bit pricey.
Conductive thermal paste will transfer heat better, but it’s highly situational whether it’s a good option. For laptops, in my opinion, it is not worth the hassle.
Why?
The word conductive explains it on its own. Basically, unless you know what you are doing, you can easily short stuff out and lose a lot of money. In addition, it doesn’t work well with all types of heatsinks, especially if you don’t consider the material they are made of.
What Can I Use if I Don’t Have Thermal Paste?
Anything homemade is out of the question. There are a lot of guides on home to make thermal pastes, and they say it’s a temporary solution, but that’s just too risky. The cheapest possible thermal paste will be a thousand times better than anything you can make at home.
The only real alternative is a thermal pad. However, thermal pads can’t always be used in a laptop. While thermal pads are fully interchangeable with thermal paste in desktops, laptops often have design and spacing issues.
Thermal Paste vs. Thermal Pads in Laptops
With the thermal pad, the CPU’s heat is not only transferred, but also a small amount of force is used to hold the cooling assembly firmly in place on top of the processor. Using paste instead of the pad reduces the amount of pressure exerted on the CPU, resulting in less effective thermal transmission.
Similarly, by providing thicker material where there wasn’t meant to be any, replacing paste with a thermal pad increases the pressure pushing down on the processor’s top and pushes the heat sink up.
In compact laptops today, thermal pads can push the cooler too far up and touch the keyboard from beneath.
3 to 5 spring screws that hold the heatsink are normally all that keep everything in place. Therefore, the springs enable the cooling system to shift and move somewhat. But there is often just a tiny amount of wiggle room in laptops.
Basically, with laptops, the safest option is to replace paste with paste and pads with pads because they are often designed for only one of those.
How Do You Clean off Thermal Paste?
Thermal paste is like grease; it’s best cleaned with isopropyl alcohol or rubbing alcohol. The difference is that isopropyl is 99.8%+ concentrate while rubbing alcohol has around 30% water.
My preference is isopropyl alcohol because it will evaporate completely. Both isopropyl and rubbing alcohol are conductive, but neither is corrosive, which makes isopropyl concentrate’s ability to evaporate completely quite a big deal purely because it’s their biggest difference, which in this case, clearly makes one better than the other.
You don’t have to worry much about spillage drops when using isopropyl.
Use only synthetic fabrics to wipe the paste off since they don’t generate static electricity.
How Do I Apply Thermal Paste to My Laptop?
Thermal paste application is usually unnecessarily complicated. Most methods end up with thick layers of paste or spillage to the side, which isn’t easy to deal with in laptops.
I’ve always had the best results with a single rice-grain-sized drop or a thin diagonal line application. Everything more complicated than that is just a waste of thermal paste and a nuisance to clean later on.
The important thing is not to spread the paste with anything. It must spread on its own when a heat sink is placed over it.
Another mistake that people often make is placing the heat sink and then lifting it again. Once you move it just a tiny bit up, in most cases, the paste will be messed up and will need to be replaced.
The surface won’t be squished properly anymore, and there will be air gaps left. You can easily check this on your own by doing a trial placement over a piece of paper. Once you see how the surface ends up deforming itself, you will understand why it has to be replaced.
Although, it highly depends on the thermal paste’s viscosity. Some pastes don’t immediately deform from small heat sink movements.
What Happens if You Touch Thermal Paste?
If a thermal paste is applied and you touch it while it’s still clumped and not spread out, you might be fine. If the heat sink was already mounted and the paste is spread, you should re-apply a new one no matter if you touched it.
As I mentioned at the beginning, thermal paste is there to transfer heat. If it’s not perfectly lining up with both surfaces, or there are air gaps and bubbles in between, it won’t transfer heat properly.
It would be best if you didn’t touch thermal paste once it’s in place, especially because your hands can leave particles on it, which will disrupt the heat transfer and possibly create gaps between the two surfaces.
Additionally, some types of thermal paste aren’t easy to remove from the skin. Wearing latex gloves while applying it isn’t a bad idea.
What Is the Cost of Replacing Thermal Paste in a Laptop?
A thermal paste costs between $5 and $50.
It’s not a difficult task to re-applying it yourself, although laptops require some knowledge of a specific model and how to reach and open certain parts of it easily.
Prices to have thermal paste changed for you vary considerably from place to place, sometimes reaching $100 for laptops.