Preheat oven to 350 degrees F (175 degrees C).
In a large bowl, mix together the cake and pudding mixes, sour cream, oil, beaten eggs and water. Stir in the chocolate chips and pour batter into a well greased 12 cup bundt pan.
Bake for 50 to 55 minutes, or until top is springy to the touch and a wooden toothpick inserted comes out clean. Cool cake thoroughly in pan at least an hour and a half before inverting onto a plate If desired, dust the cake with powdered sugar.