You probably have a short circuit somewhere within the electrical system that's draining the battery: Go to this walk thru link for more information: https://www.2carpros.com/articles/car-battery-dead-overnight

The battery does not go dead overnight. Goes dead while being driven.

I strongly suggest you have the alternator recheck and checked again to make sure its producing an output

ok alternator rechecked , everthing was fine then all of a sudden while driving lost all electrical again and batery drained while driving home , could it be bad wire or am i looking at having to change computer ? is there a way to check with out voltage meter ?