Hey Shatterstar,
Sorry to hear about your Xbox. This is a fairly common issue, and it is fixable.  I suggest you check out some videos on youtube from "My Mate Vince", "TronicsFix", or "Andrew Paul". All 3 of those guys have in-depth videos on how to solve the issue.  Most likely it's a chip on the board that's gone bad, which only costs a few dollars to replace yourself, just take your time and practice first before attempting it yourself.