Check BIOS/UEFI hardware monitor during startup
Use Windows Task Manager only for CPU usage, not temperature
Use third-party software like HWMonitor, HWiNFO, Core Temp, or Open Hardware Monitor
On macOS, use iStat Menus or Macs Fan Control
On Linux, use lm-sensors and the sensors command
Check your motherboard manufacturer’s monitoring utility
Check your laptop manufacturer’s support or control app
Use your BIOS fan/temperature screen if available
Read temperature values from CPU monitoring widgets or overlays
Compare idle and load temperatures while running a stress test