Lenovo IdeaCentre A720 - Manual (Page 48)

Step 14. Remove the 8 screws that secure the motherboard to the chassis and slide it out as shown.
Step 15. Remove the 2 screws that secure the TV-Tuner card to the motherboard.
Step 16. Disconnect the antenna cable(s) from the TV-Tuner card.
Step 17. Pull the TV-Tuner card upward to remove it from the card port.
42 IdeaCentre A720Hardware Maintenance Manual