Got a new Dell Inspiron 5555 back in November and works relatively fine until this last week when the Power Manager Lite box shows up on screen consistenly at booting up and when plugged in.  Sometimes the AC adapter shows it's plugged in and charging while other times it is not charging.  I've done everything I know to do such as check all connections and even gone into BIOS to change to "disabled" the ac power adapter warning. But still this box with Power Manager Lite keeps showing up.  Is there a defect in the warning system or is my AC adapter corrupt?  It is the same adapter (Dell 45 watt) sent with the computer in November so I don't know if that's what is the problem or not.  Also sent email to tech support but haven't heard back from them yet.  For example right now the adapter is plugged in but not charging yet it is attached correctly!  This is so frustrating!  Any advice?