Hardware Secrets posted an article about what the maximum temperature your CPU can reach without burning and how to measure your CPU current temperature.

Just like all electronic components, CPU produces heat while it is running. Heat in excess, however, isn't good and can even lead your CPU to burn or to work in an unstable way. In this tutorial you will learn what are the effects of high temperature over the CPU, will learn how to measure your CPU current temperature and will have access to tables listing the maximum supported temperature for the main CPUs available on the market.

Maximum CPU Temperature