Sony dvd rw dw-q120a dvd writing problem

Hey guys i have Sony dvd rw dw-q120a since a year now.Dn’t knw what happned.Its like when i want to write a cd it works perfectly fine & when i write a dvd it states “place a dvd in the rom”.Some time when i enter a blank dvd my pc gets stuck & i have to restart it or if it does manage to read it then i get the error that i should enter a dvd not a cd & stuff like that.I am using nero 6.
Plz help me guy

if u have intel chip set based motherboard then try to intall intel application accelator. this will to solove u r problem