To automatically decide whether or not a system board is set in a computer chassis in a correct format.

A chassis 3 in which a computer system board 5 is set can be automatically identified by forming a conductive pad 4 set at a prescribed position on the system board 5, an elastic ground clip 1 mounted on the chassis which can be brought into contact with the corresponding conductive pad 4, and a logic circuit 6 connected with the conductive pad 4. Then, it is judged that the system board 5 is set in the correct chassis, based on the contact of the corresponding conductive pad 4 with the elastic ground clip 1.