it's already dead :(

I am having a similar problem.

I am currently on my fifth Xbox 360, and just last night I got the RROD. I hate this crap. I treat my consoles like an infant child, yet they still break, EVERY TIME. I swear they build these systems out of tin cans and styrofoam. I have been though the motions before, getting the system repaired. I call 18004myxbox, they send a coffin, I send it back, they repair, It comes back. When I called this time it said (about fifteen times) to go to the webpage. So I went to xbox.com and got to filling out the forms. When I got to the serial number section I had to enter the serial number five or six times and every time it said the number was invalid. Getting frustrated, I tried one last time, and this time it told me the number was already registered. What?? WTF?!? And of course, my options end there. There are no other links to help me out with this problem, and the FAQ section of the page seemed like it was written for ten-year-olds with very little reading and comprehension skills. WTF do I do???

Also I should mention that I have not repaired this current system before. I bought an Elite because I wanted more HD space and that all-important HDMI port. This system has not been repaired before! I bought it in 2007, so my three-year warranty should still be in full swing.