Open BIOS/UEFI and check hardware monitor or system health
Use built-in diagnostics from the computer manufacturer
Install a temperature monitoring app such as HWMonitor, Core Temp, HWiNFO, or Open Hardware Monitor
Check CPU temperature in the app’s sensor or temperature section
Check GPU temperature in the app’s sensor or temperature section
Check motherboard, SSD, and fan readings if available
Use Task Manager or Activity Monitor to identify high CPU usage if temperatures are high
Compare readings while idle and under load
Check temperatures during gaming or heavy tasks
Make sure fans are spinning and vents are not blocked