Changes to the shape, size, and internal component layout of modern CPUs have made applying thermal paste, also known as thermal interface material (TIM), more complicated than it used to be.
CPUs have incorporated ever more cores and core types. Chiplets and hybrid architectures have proliferated, moving the most thermally demanding bits away from the exact center of the integrated heat spreader / lid of the CPU. And despite shrinking manufacturing nodes, many processors have just gotten physically bigger. So while you used to be able to apply thermal paste basically the same way across all consumer manufacturers and platforms and expect great results, that's no longer the case.
And let's face it: There was never any true consensus across the PC-building world about exactly what is the "right" or "best" way of applying TIM is. We all just know the wrong way when we see it. So at the risk of verging into an area of hotly contested debate, we're here to offer some simple instructions on how to properly apply your thermal interface material of choice (check our tested list of the best thermal paste) between your CPU and cooler, to achieve good thermal transfer and get that pesky heat away from your components and outside your case.
We're not saying the advice below is the absolute best method or the only correct method. We're just saying it works, and it's more or less what's recommended by PC thermal experts like Noctua and others.
Oh, and this guide is strictly for traditional thermal pastes – the non-conductive, viscous materials that make up the bulk of our best thermal paste list. Liquid Metal compounds can result in lower temperatures than most thermal pastes, but they are also usually conductive, meaning getting a drop or two in the wrong place can fry your components. And if you do get it in the wrong place, liquid metal is often much harder to remove than thermal paste – and you will need to remove it if it gets on your motherboard or other electrical components. As such, we only recommend liquid metal to seasoned PC build experts and serious overclockers.
