The opening scene featuring young Shawn is set in 1986, but one of the comic books his dad is holding is 'Checkmate' vol. 1, #28 by DC Comics, which had a June 1990 cover date. The other comic has an advertisement on the back cover for the film 'Tales from the Crypt: Demon Knight' which wasn't released until 1995.
When Shawn first surveys Malone's bedroom (at around 49 mins), the chessboard has a single soda can in the middle, the board is correctly oriented, and the chess pieces are in a (more or less) standard position. The next quick shot of the white pieces is the same. In the third shot of the board (at around 2 mins), a model of a dragon skeleton has been added to the center of the board, the pieces are randomly placed, the board is oriented incorrectly, and a different board is used (the brass plate on the front.)