My xbox turns i hear the log in sounds but it stays blank.

it might bea problem with your actual video cord that plugs into the tv.... umm my xbox has a lot of issues too but ive never had this. id suggest you let it say off for a while and try somebody elses cords that connect the xbox to the tv to see if its an issue with your xbox or if its with your cords. ill also suggest you call microsoft and they can troubleshoot...

please rate my solution :) thanks

Since your sound works, you know the xbox is booting properly.  Check two things: 1) try another television to make sure it's not the tv.  2) try another cable(from a friend?) to see if the cable is bad.
**Also, if the video settings were saved on an unsupported setting, it could cause the screen to not show video.  If you try these 2 things and you think someone might have saved bad settings, I recall a button combination you can use to reset certain things, and I try to help if it comes to that.

already solved it. thanks. i couldn't see the xbox settings blade because of the blank screen so switched my component cable to the tv setting instead of the hdtv setting, then i could see the dashboard in non-hd and switched the resolution to 720p while simultaneously switching the component cable back to the hdtv setting. that worked.

We had the same problem with ours. We had to call XBox company and we ended up shipping ours off to be fixed.

Probably you turned hdtv on change it back to tv

My solution would be to send it to microsoft if it's still under warranty.

If you can still HEAR sound, but can't see. Check your Audio Video Cable.

It's the colorful one (red, white, yellow) (red, blue green, white, red)

Make sure the connections are secure into the back of the TV as well as the connection to the back of the Xbox 360.

try using a different input on the tv or a different tv. make sure that you used a totally different av cable. if this all fails then you have an internal hardware failure

Check your AV cable if your tv is HD push the tab to HD if not set it to normal tv this should help you out. If that doesnt work i would try to borrow someones AV cable and try that.

use the towell trick! Wrap the 360 in 2 towells turn on and leave running for 15 minutes. It gets very hot but after the 15 minutes turn off the console and power it back on again and it should work. Dont know if this is a permanent fix but my 360 hasnt broken again so far. Dont ask me how but it works, google it if you like. It also cures the 3 red lights problem.