Medion Akoya Not powering on-nothing at all

Hi, I have had to use the power cable with my laptop for sometime as battery wasnt holding the charge but when I went to use it the other night, it was totally dead, nothing happened when I pressed the on button? no lights no sound no screen? so I thought it might need the battery and so I got a new battery for it, but nothing when I put in so I thought maybe it needs to charge up so left on charge overnight but no lights on laptop, tried this morning and it is still nothing? Please help its a akoyo model about 4yrs old....the power cable still has power as tested with meter. PLEASE help as it has my life on it :(