Preheat oven to 350 degrees F.
Mix sour cream, mayonnaise, cream cheese, garlic powder and 1 cup of the parmesan cheese in a bowl until smooth.
Stir in the chopped artichoke hearts.
Place in a greased baking pan (8x8 or 9x9 will work).
Sprinkle reserved 1/4 cup parmesan cheese on top.
Bake for 20 minutes or until hot and bubbly.