XBOX 360 black screen issue..

[hogfishmaster]

So I have an xbox 360 elite dated 2007-07-06. When using either the av cord or HDMI cord I only get a black screen. System powers on fine and shows all green rings. No sound or picture at all. Any guesses as to the problem. I have tried 2 av cords, and 2 HDMI cables with the same effect.

[raylydiard]

Gpu error or av port damage Microsoft can sort a repair out would be best if the void sticker is intact.