ParkControl

ParkControl is a small, free application that allows you to adjust the Core Parking of your CPU for one or more energy profiles on your machine.

You can use this application to disable some of your computer's unused cores when it's loading slowly. That way, you'll reduce energy consumption and heat dissipation. By default, Windows does not provide a direct way to adjust these parameters, which is what makes this application so interesting.

ParkControl is a tool that won't come in handy for everyone - nor will everyone know how to use. In fact, before using it, a popup window advises you to make a 'backup' of your energy configurations, just in case. Still, it can be very useful in certain cases.