A computer device includes a controller, a power supply circuit and a universal serial bus (USB) module. The controller is used for transmitting a data signal. The power supply circuit is used for supplying operating power. The USB module includes a USB bridge and a core circuit. The USB bridge is used for transmitting the data signal, and it operates according to the operating power generated by the power supply circuit. The core circuit operates according to the operating power generated by the power supply circuit.