Spread 3 cups of the chopped peanuts into the bottom of a glass 9x13 inch pan. Melt peanut butter chips in the microwave or in a saucepan over low heat. Remove from heat and stir in the marshmallow cream and condensed milk. Pour over layer of peanuts, then sprinkle the remaining 1 cup peanuts over top. Chill until set, then cut into bars.