A portable computer includes: a central processing unit; a connection chipset connected to the central processing unit and internally provided with a Universal Serial Bus (USB) controller, the connection chipset also having a plurality of ports allowing peripheral devices to be connected to the connection chipset; a Universal Serial Bus hub coupled to the connection chipset, the Universal Serial Bus hub having a plurality of connection ports allowing a plurality of devices to be connected to the Universal Serial Bus hub; and a switching circuit connected between the Universal Serial Bus hub and the Universal Serial Bus controller, the switching circuit serving to transmit an output signal from the Universal Serial Bus controller to the Universal Serial Bus hub when at least one of the devices connected to the Universal Serial Bus hub is driven. A control method for the portable computer provides a control function for allowing or cutting off the transmission of the output signal from the Universal Serial Bus controller to the Universal Serial Bus hub in accordance with whether or not at least one of the devices connected to the Universal Serial Bus hub is driven. In accordance with this configuration, the central processing unit can be maintained in a C3-state insofar as the Universal Serial Bus hub is mounted in a fashion meeting the ACPI specification. Therefore, it is possible to achieve a reduction in power consumption.

 
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