After testing different patterns on multiple CPUs, I found that the X-pattern yielded the best results for larger processors like the Threadripper. But for most other processors, anything more than a tiny dot was excessive.
The pea method is one of the best ways to apply thermal paste. This involves putting a pea-sized dot of paste in the middle of the CPU before attaching the cooler.
The paste then spreads out evenly when pressure is applied from installing the cooler, creating a thin layer that fills in all the microscopic gaps between the CPU and the cooler surface.
Other commonly used patterns are 5-dots, single/double/triple lines, and buttered toast. All of these come with their individual pros and cons.
Now, let’s discuss all these patterns in detail.
I have also tested the spread by placing plastic sheets between my thermal paste (HY510) and the heatsink to illustrate better how it spreads.
X-Pattern or Cross
The X-pattern is one of the most popular thermal paste patterns and for a good reason. Here, you apply the paste as two diagonal lines by forming a cross.
This way, the paste on each line spreads sideways when installing a cooler or heatsink and covers most of the processor.
- Good overall spread on the processor.
- Very less chances for air pockets.
- Suitable for thermal paste with low to medium viscosity.
- Best option for larger CPUs
- Chance of spilling thermal paste from corners.
- Difficult to judge the most suitable amount of paste.
- Not ideal for thermal paste with high viscosity.
- Unsuitable for electrically conductive thermal pastes like liquid metal.
Note: The viscosity of a thermal paste affects its spread. A less viscous thermal paste spreads further while making a thin layer but can easily spill to the motherboard with an incompatible pattern.
A more viscous thermal paste doesn’t spread as much. So it may create thicker spots where you apply it. And it requires a more spreaded pattern. But it doesn’t spill as much and is easier to clean from the cooler and the CPU.
Best Way to Apply:
- Make the width of each diagonal continuous but as thin as possible.
- Don’t let the ends of the ‘X’ go all the way to the corners.
Pea or Dot (Blob)
Another way to apply the thermal paste is by putting a pea or dot of it in the center of the processor. After installing the heatsink, the paste spreads outwards in all directions from the center.
The dot is usually pea-sized for standard CPUs. For CPUs with larger socket sizes, you may need a bigger blob. If you are applying the paste to a processor without IHS, a rice-grain-sized dot should be enough.
- Easiest to judge the necessary amount and apply.
- Least chances of spilling the thermal paste.
- Thermal paste lasts longer.
- Suitable for thermal paste from low to high viscosity. But works best with medium viscous pastes.
- Suitable for most processors, including delidded ones.
- May not spread to all the surface of the processor, especially its corners.
- May be thicker in the middle, increasing the overall thermal resistivity.
Best Way to Apply:
- Just squeeze a suitable amount of paste according to the size of your CPU die or IHS.
- Avoid shaking the thermal paste tube too much, or some air pockets may form. Having the least air pockets prolongs the thermal paste’s lifespan.
Buttered Toast
You can also use a thermal paste spreader to spread the paste all over the CPU surface. Here, you are not relying on the heatsink to spread the paste but doing it yourself.
Depending on how you spread the paste, it can have a rough or smooth surface texture. But smooth is always preferable as a rough spread can create air pockets.
These pockets increase the overall thermal resistivity of the layer, consequently overheating the CPU and reducing its lifespan.
- Best spread over the processor surface.
- Ideal for thermal paste with medium viscosity.
- Low possibility of spilling to the sides if you use a proper amount.
- Time consuming to apply properly.
- Highest chances to form air pockets.
- Difficult to decide the suitable amount.
- Can spill with higher amount or if you use pastes with low viscosity
- Unsuitable for electrically conductive thermal pastes.
Best Way to Apply:
- Apply the paste on one side as a straight, continuous line. Then, spread it slowly to the other side.
- Use a regular Thermal Paste Spreader instead of looking for alternatives.
- Make the spread as smooth as possible to limit possible air bubbles. More air bubbles will cause the paste to dry out sooner.
- Try not to spill the thermal paste to the motherboard while spreading.
- After mounting the heatsink, it’s better to check if the paste contacts its base properly to confirm the necessary amount.
Single Line
Many people also apply the paste in a single straight line from one side to the other. It acts similar to the dot pattern, but the spread in all directions is more uneven.
- Easy to judge the necessary amount and apply.
- Less chances of air pockets.
- Good option for thermal paste with low to medium viscosity.
- May not spread properly to all the sides and corners.
- Can spill on the sides closer to the ends of the line.
- May be thicker in the middle, increasing the overall thermal resistivity.
- Not suitable for thermal paste with high viscosity.
Best Way to Apply:
- Don’t let the ends of the line touch the sides.
- You can apply the paste either vertically or horizontally.
- Don’t make it too thin or too thick. It’s better to test out the spread before the final application.
Double/Triple Lines
Since a single line doesn’t spread the paste much to the sides parallel to the line, you can apply more lines for a better spread. In this pattern, you put the thermal paste as two or three parallel lines symmetrically on the CPU.
You need thinner lines if you want to use the triple-line pattern. However, everything else remains the same between these two patterns.
- The paste will spread to all the sides.
- Somewhat even thickness all over the layer.
- Good option for thermal paste with low to medium viscosity.
- May not spread to the corners.
- Can spill on the sides closer to the ends of the lines.
- Some chances of air pocket formation.
Best Way to Apply:
- Make each line continuous and thin.
- Don’t let the lines touch the sides.
- You can similarly apply the paste vertically or horizontally.
5-Dots
You can also apply five dots of the thermal paste on the processor so that it spreads to the whole surface after you mount a heatsink. Four dots go to the corners, and the final one goes to the center.
- Easy to apply.
- Good even spread over the processor.
- Suitable for bigger processor chips.
- Good option for thermal paste with medium viscosity.
- Less chances of spillage.
- More chances of air pocket formation.
- Slightly difficult to judge the necessary amount.
Best Way to Apply:
- Apply a small dot-shaped thermal paste on the center.
- Apply four smaller dots near the middle point between the center dot and the corners.
Testing Out the Patterns
I also tested out the results of different HY510 thermal paste patterns on an Intel CPU under the same environment conditions. I tried out all the patterns multiple times with varying amounts of paste and monitored the CPU temperature.
I have illustrated the best result for each pattern in a comparison graph. I did not compare patterns using the same amount of paste as it spreads differently for separate patterns. So the comparison would not be fair.
The components that I used included,
- Processor– Intel i3-12100 (no OC)
- CPU Fan– Intel Stock Fan
- Motherboard– MSI PRO B760M-E DDR4
- Thermal Paste– HY510
From the comparison graph, we can see that there’s not much difference in the CPU temperature.
In the idle state of the CPU, the temperature ranged from 34-38.5°C. On running a single core stress test, the temperature remained between 49.3 and 54.6°C.
Regardless, I got the best result from the pea pattern, closely followed by the cross.