The System tool in Control Panel uses currentspeed to do its reporting rather than maxspeed, but the System tool may display the wrong clock speed for the Central Processing Unit (CPU).

As of January 2002, Windows XP uses the currentspeed value rather than the maxspeed value because the maxspeed value was reporting inconsistent values.

After startup, the processor may not correctly reflect its correct speed until a program utilizes processor cycles.

The computer basic input/output system (BIOS) in some laptop computers may throttle the processor because of heat, load, power AC/DC.

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