Why do I have to hold down the power button to turn off my PictureTel 600?

The PictureTel 600 Series system uses a mainboard and BIOS configuration that implements the ACPI (Advanced Configuration and Power Interface) Specification. This specification dictates that the "power button" on the system is used to initiate a logical response from the system which is predefined in BIOS or software. In order to force an override and power off the unit completely, you must hold the power switch in for approximately four seconds or more depending on the implementation of the standard. This is normal for the PictureTel 600 system.