I have the acer 1703 laptop with the matshita uj-811b dvd-r, recently it stopped working so i went to a computer shop and bought the lg gms-4082n dvd-r, which seemed to fit BUT when i put it on the laptop it does not recognie it...what can i do about that????? is the bios locked or something??? can i do anything to make it work or i should buy the same dvd-r???