I found that I have to push the reset button on the microcontroller board or start the serial communication with computer to "light up" the Gameduino board. Is this a common procedure or because the microcontroller board I was using is not the proper one? Also I would like to ask if there is a way to directly start the Gameduino without pushing the reset button or by initiating the serial communication. Thank you!!
I don't know why, but the problem has been solved. I found the Gameduino 3 can successfully power on without pushing the reset button of Arduino. (Maybe it is not working a default setting on Gameduino 2?)