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Computer will not automatically reboot after UPS has shutdown and restarted

Issue:
Computer will not automatically reboot after UPS has shutdown and restarted

Product Line:
PowerChute Personal Edition
PowerChute Business Edition
PowerChute Network Shutdown

Environment:
All devices that include BIOS
All APC UPS

Cause:
This problem is independent of the type of UPS connected. It is a function of

the BIOS implementation supporting the soft-switch on computers. It is not a

problem with APC UPS's or with PowerChute.




Solution:

To resolve this, change this BIOS setting, if possible, to Last State. If you cannot modify this setting, then the UPS will not be able to automatically reboot the computer under any circumstances - with APC or any other UPS.

Please contact your computer or BIOS manufacturer to find out if it is possible to change this BIOS setting on your particular computer and for exact instructions on how to do so.

NOTE: If the system OS is Windows 2003, 2008 or 2012 please review Kbase FA159604

Background:

Most new computers available in the market today use the ATX motherboard which supports the use of a soft switch to turn the Computer On and Off. The implementation of this soft switch includes a BIOS parameter which defines the state the computer will enter when the power supply senses input power when plugged into the wall. This BIOS parameter can have any one of three values :

ALWAYS ON: When power is cycled on, the computer will automatically turn on and boot up.

ALWAYS OFF: When power is cycled on, the computer will stay off until the user manually hits the On/Off soft switch.

LAST STATE: When power is cycled on, the computer will either come on or stay off depending on whether it was On or Off when the power was lost.



Most computer manufacturers set this parameter to Last State and some computer manufacturers set this parameter to Always Off. It is highly unlikely to find the Always On parameter setting. In many cases, the computer manufacturer permits the user to change the value of this parameter by using the system setup menu which can accessed prior to the operating system loading when the computer is turned on.

If this parameter is set to Always Off then an APC UPS cannot reboot this computer as it will not turn on when the power is cycled independent of the state of the PC prior to power being turned off.



 
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