Hey good question! Therefore, yes, at boot, when your PC loads, you can look at your BIOS/UEFI ( find something in there that says Hardware Monitor or PC Health Status ) and in some motherboards, the core temperatures of the CPUs will be displayed. However, the minute you start using windows you will feel the need to have some monitoring utility. I operate the free and lightweight Core Temp and it displays the temp of each core in real-time. It is just necessary to install it, run it, and you will see the numbers. Unless your idle temperatures are below, say, 50 degC, and your load performance falls below, say, 80-90 degree (depending on your CPU), then you are fine. When you are seeing crazy figures you would want to inspect your cooler, airflow etc.