A card edge connector includes a contact assembly received in a cavity of a housing. The contact assembly has a contact positioner holding upper and lower contacts. The contact positioner has an upper wall with upper contact channels holding mating beams of the upper contacts and a lower wall with lower contact channels holding mating beams of the lower contacts. A positioner card slot is defined between the walls receiving a card edge of a module circuit board. The upper wall has pre-load beams in the upper contact channels engaging the mating beams of the upper contacts to pre-load the upper contacts in an inward biasing direction and the lower wall has pre-load beams in the lower contact channels engaging the mating beams of the lower contacts to pre-load the lower contacts in an inward biasing direction.