Do you know of a macro or app that will beep when CPU usage dips below a set %?

Sometimes my SolidWorks takes several minutes to complete a task or function and during that time its CPU usage is "12%" or higher.

I would like a PC app or program that will beep when the CPU usage goes below 5% (for example) so I know to return to SolidWorks and continue working.

Otherwise, it's a big time suck to continually check SW if it has completed its task.