Puppy food amount

We just got an almost 4 month old golden doodle and are feeding him Diamon Naturals Large Breed Puppy food. The bag says to feed him 4 or 5 cups of food a day. His old owner was doing Purina Puppy Chow :(, 1 cup, 2x a day so I started with 1 cup of Diamond 2x a day. He has had large poops 2-3x a day with that amount. Should I really increase to 4-5 cups a day and if so how should I split it up over the day