most likely Video Encoder IC failure (shorted to GND on Pin 13 of HDMI port/CEC), APU failure usually presents itself differently when system still boots to the main menu (after the game is launched, the picture will have artifacts, and the system will freeze almost immediately on distorted image).
If unsure, to test whether you have APU or Video Encoder IC failure, use Optical cable for audio output, launch the game, and after screen goes black - listen if you still have sounds of game loading into the game menu. But, if you don't hear any sounds and can't turn off the system by pressing the power button (doesn't beep at all when power button is pressed and held) - then it has APU failure