Spread 1 package corn chips on the bottom of a greased 13x9-in. baking pan; sprinkle 1 cup chocolate chips over the top.
In a large heavy saucepan, combine sugar and corn syrup. Bring to a boil; cook and stir 1 minute. Remove from heat; stir in peanut butter. Pour half the peanut butter mixture over chip mixture. Top with remaining corn chips and chocolate chips; drizzle with remaining peanut butter mixture. Let stand until set. Cut into bars.