The correct way to apply the best thermal paste has been a hotly-contested topic among PC enthusiasts since PC DIYing began. Some people swear that the best application method is in a central blob, a cross, a line, more complex patterns, or even spread on the chip like butter on a cracker. Igor Wallossek of Igor’s Lab sought to test and demonstrate the best method of thermal paste application for GPUs, not CPUs. Igor found that the best method resulted in a liquid-cooled GPU which ran five degrees Celsius cooler than the least favorable method.
In what is, in essence, Igor’s GPU re-pasting guide, he starts by talking about how important correct thermal paste application is on large GPUs. Smaller GPUs are more forgiving, but larger, more powerful ones have uneven surfaces and may suffer from warping when under the tension of the cooling assembly. We have seen similar tales of warping recently with the elongated Alder Lake CPUs, which are thermally improved by the use of mounting frames.
Igor also stresses the importance of cleaning off the old thermal paste properly. He provides a walkthrough of his methods, what to look out for, and what to not fuss about.
Interestingly Igor asserts that due to the ‘brutal’ gaps between a GPU and a cooler, using a high-viscosity thermal paste is essential. For GPUs, he emphatically dismisses popular products like Arctic MX-2 or MX-4 but puts a good word in for Alphacool Apex or Subzero or “the old Gelid PC Extreme.”
Before applying the paste to the GPU, you should try and get it to a ‘hand-warm’ temperature, and the same applies to the GPU. Igor suggests putting the thermal paste tube in a pocket for a few minutes and checking the GPU die isn’t ice cold. Before and after application, a bit of hair dryer action might help keep the viscous paste easily workable.
On the controversial topic of thermal paste application shapes, Igor tested a GPU that was fully ‘painted’ with paste vs a central blob vs a vertical line (the titular sausage). Sadly he missed out on the central cross and several other popular methodologies/permutations. For example, look at Noctua’s CPU pasting recommendations which came to light earlier in the week.
Sausage Wins, but Relies on a Seesaw Screw Tensioning Method
The sausage-style central vertical line was the easy winner in Igor’s tests. However, its use is wedded to a particular method of screw tensioning. First, when re-attaching the cooling assembly, you must place it straight down onto the GPU without sliding around. Then you must apply a little tension to one side pairing of screws, followed by the other side, then back and forth a few times – working it like a seesaw.
In his tests, the sausage method was quite an obvious winner, offering about a five degrees Celsius improvement over other methods. Igor says he used liquid cooing for consistent results with his GeForce RTX 3080 reference PCB.
Wrapping up, Igor stands solidly by his pasting and cooler tensioning method, saying some manufacturers follow a very similar method to that outlined above. Perhaps readers can try this methodology next time they re-paste an old GPU. Let us know what you think in the comments below.
There are so many thermal pastes to choose from in 2022. If you are confused by the choice, it is worth having a look at our best thermal pastes roundup, considering 90 products.