Xbox HDMI for video, AV ports for sound, Xbox shuts down if both are in at once.
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Xbox 360 Standard HDMI Cable - Unboxing PL/ENG - YouTube
How to: Connect Xbox 360 AV & HDMI at the same time - YouTube
HDMI cable - Xbox 360/360 S Accessories - SOSav English
Amazon.com: Xbox 360 HDMI Converter, Xbox 360 to HDMI Converter HD Link Cable for Xbox 360, Xbox 360 to HDMI Support 720P / 1080P. Compatible with Xbox 360 and Xbox 360 Slim. : Video Games
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