Jordan Storey and Ched Evans found the net either side of half-time, with North End keeping another clean sheet - a fourth on the spin.
Victory in their final home game of the season moved the Lilywhites up to 13th place in the table.
Here are the player ratings from the game, with centre-back Storey the starman.
13. Brad Potts 6
Replaced Whiteman with eight minutes left, miskicked in the box when Evans laid the ball back for him. Photo: Camerasport
14. Tom Bayliss 6
A stoppage-time cameo from Bayliss as a replacement for Evans. No time to make an impact. Photo: Camerasport
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