After flashing bios, aero starts up without wireless, hdmi output and usb output

[leomoons]

I just followed the official video tutorial on youtube. During the process of flashing bios, the output of hdmi and usb disappeared. And I can't shut down the intel board through the button(5 seconds). The only way I can turn off the board is unpluging the Li-po battery. I've tried wireless method to connect to the board but failed. Is there anyway to flash the board and back to the initial condition?