Processor may have up to 15% usage when the system is idle on Windows XP x64 edition

Source: Microsoft Support

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On a system running Windows XP x64 edition, let the system run idle, and do not touch the mouse or keyboard.

Up to 15% of the processor may be used while the system is idle.  Moving the mouse, or pressing a key on the keyboard should cause the usage to drop to 0-5% as the system will no longer be in an idle state.

This is caused when extended advanced power management features are enabled in the BIOS on a system with a dual core processor.  This problem has not been observed on single and quad core processors.

To resolve this issue, disable any extended power management options in the BIOS.

There is no performance degradation as this only happens when the system is at idle.

Please contact your BIOS manufacturer for information on how to disable power management features in the BIOS.

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