Patent ID: 8001312

Claim:
A circuit board system for connecting with at least an expansion card, comprising: at least an expansion slot for connecting with the expansion card; a Programmable Logic Device (PLD) electrically coupled to the expansion slot; configured to detect whether the expansion card is compatible with the circuit board system, and outputting a detecting result; a logic controller coupled to the expansion slot and the PLD; and a main power supply electrically coupled to the expansion slot via the logic controller; wherein when the PLD detects that the expansion card is not compatible with the circuit board system, the logic controller cuts off the connection between the main power supply and the expansion slot; the expansion card comprises a present code and ID code, the PLD stores a plurality of expansion card ID codes of different expansion cards which can work with the circuit board system; and the PLD is configured to detect the ID code of the expansion card, and compare the ID code with the stored expansion card ID codes to determine whether the expansion card is compatible with the circuit board system; wherein the PLD is configured to output a control signal to the power controller to control the main power supply to provide power to the circuit board system after receiving a trigger signal if the ID code's logical numbers are all high voltage level.