A PCI load card includes a PCI interface, an operational amplifier, at least two switches, and a controller. A terminal of each switch is connected to an input terminal of the operational amplifier and connected to a standby power pin of the PCI interface via a first resistor. The other terminals of the at least two switches are respectively connected to ground via at least two resistors. The other input terminal of the operational amplifier is grounded. An output terminal of the operational amplifier is connected to a first terminal of the controller, a second terminal of the controller is connected to a system power pin of the PCI interface, a third terminal of the controller is grounded, the power of the controller is adjusted by controlling the at least two switches.