Rebellion88

To be honest bad connection through a cable would be a long shot because you would have noticed the screen flicker or play up before hand. Overheating could of caused something, was the laptop doing anything when you left it on, or was it in cool place? You could strip it and see if there's any signs such as capacitors leaking, check the wiring. You can even try a local electrician or a tv repair shop, they may find the problem. You could try stressing the the grpahics card by playing a game see if anything happens.