Dell Monitor Help!!

Hey,

I have a dell 17" monitor, i have bought a VGA HD Av cable so that i can connect it through my xbox 360, but when i start the xbox, there is no display on the screen, to make sure that the cable is working properly, i attached it to my TV and it was working perfectly, and to make sure that the monitor is proper i attached my computer with it, and the display was proper, i am really confused what the problem is and what is the solution.

It would be great if anyone one of you will help me. I can also pay one of you if you come to my house and solve my problem.

Thanks in advance

Tell us what model your monitor is and what cable you have purchased and we maybe able to offer some useful suggestions.