Definition: Thermal paste (also called thermal compound or thermal interface material) is the heat-conducting paste applied between a desktop CPU die and the base of its cooler. It fills microscopic surface irregularities to maximise heat transfer. Without it — or with dried-out paste — CPU temperatures rise, causing thermal throttling and reduced performance. Desktop CPUs also have a spreader (IHS) between the die and the cooler, unlike most laptop CPUs.
Why desktop thermal paste differs from laptop
Desktop CPUs have a metal heat spreader (IHS — Integrated Heat Spreader) on top of the die. Thermal paste sits between the IHS and the cooler. Some enthusiasts also delid the CPU (remove the IHS) and replace the paste between the die and IHS — this can reduce temperatures by 10–20°C on older Intel CPUs that used poor quality stock TIM.
Desktop CPUs run hotter than laptops because they have higher TDPs and more thermal headroom. A Ryzen 9 7950X has a 170W TDP. Even with a high-quality cooler, dried thermal paste causes temperatures to climb beyond 95°C and trigger significant throttling.
When to replace desktop thermal paste
- CPU temperatures consistently above 85°C at idle or light load
- System hasn’t had thermal maintenance in 3–5 years
- After removing the CPU cooler for any reason (CPU swap, cooler upgrade)
- Visible dried or cracked paste when cooler is removed
- After delidding a CPU
Recommended thermal pastes
- Arctic MX-4 / MX-6: Non-conductive, easy to apply, excellent performance. BreakFixNow uses MX-4 as standard.
- Thermal Grizzly Kryonaut: High performance, slightly better than MX-4 in demanding scenarios. Available on request at BreakFixNow.
- Thermal Grizzly Conductonaut (liquid metal): For delid applications only — electrically conductive and will damage components if applied incorrectly.
Related terms
- CPU Socket — thermal paste is applied after CPU is seated
- PSU — an overheating CPU from bad thermal paste can trigger PSU-level shutdowns
- Thermal Paste Application Singapore — professional service at BreakFixNow
Desktop running too hot?
BreakFixNow replaces CPU thermal paste on desktops from $40. Walk in — no appointment needed.
BreakFixNow replaces CPU thermal paste on desktops from $40. Walk in — no appointment needed.