Hi jbkendall,
Please check if the green light stays on, on the Ac adapter when connected to the system. If the LED stays on, I suspect the motherboard is faulty. However you may try with a known good Ac adapter before considering replacing the motherboard. In case the system is under warranty, send me a private message with the system service tag to assist you further. Please click on my name and click Start Conversation to send me a private message. Please click on the link below to check the warranty of the system:
In case the system is out of warranty, let me know the region you belong to, to provide the contact information to get the system serviced.