This is Mani from the Dell social media Team,
In order to determine if it is a software issue you can check for the error if any that is causing the computer to restart, you need to disable automatic restart. This is in the advanced tab of system properties under startup and recovery. Also check event viewer for any errors. These are the steps you can perform to isolate if the issue is related to the motherboard or any hardware component.
The system over heats
Beeps when it restarts
Please post back and let me know if you need more help.
Thanks and regards
Social Media Responder