Xbox Videos Games Free Download

So I just bought Turtle Beach today, hooked it up with the audio cords, didn’t plug in the yellow video cord, went to plug in the HDMI cord, and it didn’t fit, there is a bumber like looking thing on the AV cable output… Tried to saw it off, and gave up, told myself I’d have to get used to not so good resolution. So I launched Battlefield 3, and its in widescreen… Is there any way to fix that?
And is there any other way to use the turtle beaches and an HDMI, or would my best bet be sawing off the bumper? And if it matters, I have the newer version of the xbox