UDK bad performance on laptops?

We’re making the experience that our UDK based game runs with unreasonably low FPS on laptop gtx cards (those with an M after the number, like “gtx 970m” or so).
People with normal desktop graphic cards easily get 100-200fps. The mobile people get 10-40fps.

Do you have any experience with this? Are we doing something wrong or is UDK just like that?