Actually the ideal CPU performance is dependent on the processors that you are using.
In general The optimal performance for most of the processors is 50° Celsius (122° Fahrenheit) or below.
Most CPUs' maximum temperatures are around 100° Celsius (212° Fahrenheit).This is the maximum temperature any processor can go up to but before
you get to that upper limit your laptop will likely to have problems like:
- performance problems
- shutting down randomly on its own.
These softwares are called free monitoring programs and available on internet.
There are many software which can monitor the core temperatures of your CPU.
If you are not getting any kind of overheating problems then it is a sign that your computer is running smoothly.
If you want to check the temperature ratings of various computers then go to the following links: