How to view CPU clock rate in GHz?

I am looking to get the new 12″ MacBook and as a result I would like to know the clock speed (in GHz) my MacBook Air is running at so I know the processor on the MacBook will cope.

At the moment I know my processor running at the lowest frequency is 1.86GHz (as shown in System Information) and when I look in Activity Monitor as suggested here it only shows me the CPU usage and not the current clock speed. I have also looked at this suggestion but again it does not show me my processing frequency.

The reason why I want to find out the current speed my MacBook Air is running at is because Turbo Charge (explained here) means the clock speed is not the same all the time.

Edit Thanks @grgarside for the suggestion of application however my CPU is not supported as suggested here.

The MacBook I have is a late 2010.