Pause Windows when possible is a feature designed to automatically pause a Windows virtual machine to save your Mac resources. Pausing Windows virtual machine releases CPU resources which are currently used by Windows. Then released resources can be used again by the Mac, its applications or by other virtual machines on the computer. If you select this option, the virtual machine will be automatically paused if:

• The virtual machine is running, but its window is not active for more than 30 seconds

• There are no applications running in Windows (no icons of Windows applications are present in the Dock)

To manage this feature navigate to the virtual machine's configuration:

Go to Options tab > Startup and Shutdown > check the Pause Windows when possible option.

NOTE: This option is available only when Parallels Tools are installed in Windows virtual machine and Isolate Mac from Windows option is disabled in the Security tab.