Preheat oven to 350ºF. Generously grease bottom and sides 10-inch springform pan.
Combine cake mix and oil in large bowl. Mix well. Press onto bottom of prepared pan.
Bake 22 to 25 minutes or until set. Remove from oven. Increase oven temperature to 450ºF.
While crust is baking place cream cheese in large mixing bowl. Beat at low speed with electric mixer, adding sugar gradually. Add sour cream and vanilla extract, mixing until blended. Add eggs, mixing only until incorporated. Toss 1/2 cup chocolate chips with flour. Fold into cream cheese mixture. Pour filling onto crust. Sprinkle with remaining 1/4 cup chocolate chips.
Bake 5 to 7 minutes. Reduce oven temperature to 250ºF. Bake 60 to 65 minutes or until set. Loosen cake from side of pan with knife or spatula. Cool completely in pan on cooling rack. Refrigerate until ready to serve. Remove side of pan.