Preheat oven to 350 degrees. Spray a 12 cup bundt pan with Pam and set aside.
In a large bowl, combine cake and pudding mixes, sour cream, oil, beaten eggs, and water. Stir in chocolate chips and pour into prepared pan.
Bake 50-55 minutes or until top is springy to the touch and a wooden toothpick inserted comes out clean. Cool completely in pan at least 1 1/2 hours before inverting onto a plate. If desired, dust cake with powdered sugar before serving.