SpeedswitchXP is a small applet that sits in the system tray and allows dynamic switching of the frequencies of mobile Intel and mobile AMD CPUs under Windows XP. During the development of Windows XP, Microsoft decided to integrate dynamic frequency switching into the operating system itself. On a default Windows XP installation, the power schemes in the power settings of the system panel control the frequencies of the processor. On Windows 2000 and previous operating systems, it was possible to manually control the CPU frequencies with a SpeedStep applet provided by Intel, but this is not possible anymore under Windows XP.