Hi Christof,

OpticStudio does not have a limit on the amount of CPU's it can use. The program will be able to 'see' all available CPUs on your machine; however, this does not automatically mean that OpticStudio will utilize all of the open cores. In general, OpticStudio is built to determine the optimal number of threads necessary to perform the current calculation. It will only use what it needs. This is discussed in more detail in the following forum posts:

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  Why does the CPU usage on my computer seem to be single-threaded during optimization?

  
  


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  CPU usage is low during optimization

  
  

In addition to this constraint, Windows itself may also limit the amount of resources any one program can take. This setting is usually manually set - often by a company's IT department - and can be changed through the Task Manager. 

Let us know if you have any other questions about this!

Best,

Allie