if you know the key to press for the bios keep it pressed as you apply the power and with luck it will open. As you have opened the laptop up try disconnecting the dvd drive in case it has shorted out. Being just out of warranty does not alter the fact that the equipment should be of purpose. Try the place you bought it from and if you tell them that you intend getting an independant report on the problem and will then take action against them you generally get somewhere. In England you have up to 6 years to claim for something not fit for purpose it is only 5 years in Scotland.