Thermal throttling is when a chip reduces its clock speed to prevent overheating. Devices with poor cooling can lose 20–40% of peak performance under sustained load.
When CPU/GPU temperature exceeds the thermal limit (typically 90–100°C), the chip dynamically lowers voltage and frequency. Performance drops, sometimes substantially.
Mobile devices have minimal cooling (no fan), so flagship phones throttle quickly under heavy gaming. Active cooling accessories or vapor chambers in gaming phones reduce throttling.
Laptops use heat pipes + fans; gaming laptops add vapor chambers and dual-fan designs to reduce throttling. When comparing performance, check sustained-load scores instead of single-shot benchmarks.