I was changing my laptop screen on an advent roma 1000 model. While the old screen was out i switched on the laptop (with no screen) and it just went dead. The power button stopped working, it wouldn't even light up. I fit the new screen in anyway and got it checked out from a pc shop. They told me the motherboard had gone, so i bought a new motherboard for it. I replaced the motherboard myself - now the power button lights up but it doesn't boot up. The power light just goes on and off. Is someone able to explain what's happened?