@ryder5547 check your monitor. All of this sounds like a bad backlight (except the going grey-black colour). Let's rule that out.Try this:
Turn your xbox on and see if you can remember how to start a game etc. (it will be great if you get to a point where you hear the sound).. Next, use a flashlight and shine the beam at an angle against the screen. Do that in a darkened room. See if you can make out shadows or shapes of your desktop. If you do, then it is your backlight that has failed.
Let us know what monitor you are using.
Of course there is always the possibility that this is an HDMI issue, Use a new/different cable as well.