Abstract: A casing includes a base, a trigger switch, an alarm device, and a cover. The base includes a first side plate and a second side plate perpendicular to the first side plate. The trigger switch is mounted to an inner side of the first side plate. A resilient tab is formed on a top of the trigger switch. The alarm device is electrically connected to the trigger switch. The cover covers on a top of the base and deforms the resilient tab down. A recess is defined in a bottom surface of the cover and located between the second side plate and the resilient tab. When the cover is slid away from the second side plate, the recess aligns with the resilient tab. The resilient tab enters the recess and restores. The trigger switch triggers the alarm device to alarm.

Abstract: A fixing member for fixing a riser card with an edge connector includes a board for fixing the riser card, and a blocking piece connected to a bottom side of the board and adjacent to the edge connector. The blocking piece is arranged to abut a top of an expansion slot longer than the edge connector, to prevent the edge connector from being inserted into the expansion slot.

Abstract: A casing includes a base, a trigger switch, an alarm device, and a cover. The base includes a first side plate and a second side plate perpendicular to the first side plate. The trigger switch is mounted to an inner side of the first side plate. A resilient tab is formed on a top of the trigger switch. The alarm device is electrically connected to the trigger switch. The cover covers on a top of the base and deforms the resilient tab down. A recess is defined in a bottom surface of the cover and located between the second side plate and the resilient tab. When the cover is slid away from the second side plate, the recess aligns with the resilient tab. The resilient tab enters the recess and restores. The trigger switch triggers the alarm device to alarm.

Abstract: A fixing member for fixing a riser card with an edge connector includes a board for fixing the riser card, and a blocking piece connected to a bottom side of the board and adjacent to the edge connector. The blocking piece is arranged to abut a top of an expansion slot longer than the edge connector, to prevent the edge connector from being inserted into the expansion slot.

Abstract: An electronic device includes a motherboard and a chip module. The motherboard includes a first connector. The chip module includes a circuit board parallel to the motherboard, a chip mounted on the circuit board, a second connector, and a fastener. The second connector of the chip module is electronically connected to the first connector of the motherboard. The fastener extends through the circuit board, to fix the chip module compactly and firmly in place.