Depends on your cooler (or really more the socket which determines the amount of pressure the cooler puts in the IHS) and the paste you use. Some thermal paste, especially high performance ones, are more vicious. Over time with the pressure from the cooler it'll "pump out" as they call it.
Even if that doesn't happen to you, paste will dry out and reduce its effectiveness. Neither of these are a concern with PTM phase change pads. Those things will last for years.
I'd look to replace thermal paste like every 2-3 years or so, or if you notice your cpu temps climbing.
Depends on your cooler (or really more the socket which determines the amount of pressure the cooler puts in the IHS) and the paste you use. Some thermal paste, especially high performance ones, are more vicious. Over time with the pressure from the cooler it'll "pump out" as they call it.
Even if that doesn't happen to you, paste will dry out and reduce its effectiveness. Neither of these are a concern with PTM phase change pads. Those things will last for years.
I'd look to replace thermal paste like every 2-3 years or so, or if you notice your cpu temps climbing.