Electrical Engineering is the field that nurtures the methodology of using Electricity , Electric Materials , Magnetic fields etc where as computer engineers develop computers and systems architecture.

Now when this two topics are adjoined then the field ECE is mainly all about developing Computer system more efficient  by using innovative thoughts in the Electrical supply and more supremely making the system more efficient to perform.

Thus if you have a interest in building Computer Hardware this will be a great course for you.

Hope my answer helps you. Have a great day!