Mac users interested in Cpu frequency monitor for intel mac generally download:
MacCPUID is a utility created to help you find detailed information about your processor. The program features a straightforward interface, gives you access to accurate details, and enables you to export the offered information with just a few clicks.
CPU History is an application that graphs your current CPU usage history in the Dock icon, and optionally, in a floating window. You can customize colors, update frequency, and bar thickness.
It uses very little CPU to monitor your CPU usage. I think this is a good thing.