Thermal paste is not designed to dry out quickly as it needs to remain viscous and get spread over the entire CPU. This helps fill any microscopic gaps to maintain an effective heat-exchange system.
However, over time, it eventually dries out due to its composition and constant cycles of exposure to high heat.
Standardthermal paste lastsabout 2-5 years,and high-quality ones can support your CPU for a few more years. Cheaper, low-quality pastes, meanwhile, will only give you at most a couple of years of good performance, after which the paste will start to dry.
Even before completely drying, the paste can start deteriorating with time. So I usually replace the thermal paste on my PC after 2-3 years so that it doesn’t completely dry out and affect the CPU.
How Long Does Thermal Paste Take to Dry on a CPU?
Most thermal paste usesorganic solventsto mix all of its components and have them in a fluid or pasty state. These solventsevaporate with time, especially due to constant heat cycles from running your PC, and cause the paste to become dry.
Thermal pastes that use non-organic solvents are also available in the market. But they just prolong the rate of solvent evaporation and can’t entirely negate it.
The rate at which such a process occurs depends on many factors, such as:
Due to all these factors, most thermal pastes will dry out after2-5 years of use.Higher quality ones, especially those that have non-organic solvents, will last6+ years,depending on your usage and placement.
What Happens When Thermal Paste Dries Out?
The purpose of thermal paste is to fill in any gaps between the CPU’s IHS (lid) and the metal surface of the CPU cooler. While it is not as good a thermal conductor as metal, it is much better than air, and its fluid nature makes it a good interface for heat exchange.
When the paste dries out, it getscrumby,and you’ll usually seecracksin the dried compound, which creates more pockets of air between the CPU and the heat sink. Consequently, the heat can’t dissipate to the heat sink as effectively, and yourCPU will start overheating.
Your CPU fan will also start compensating for the increase in theCPU temperatureand run atfull speed, causing alot of noise.
How to Prevent Thermal Paste from Drying?
It is not possible to completely prevent thermal paste from drying. What you may do is prolong its lifespan by limiting all the factors that affect the rate of drying. For that,
