HERE IS SOME ADVICE FOR BUYING "OEM" DVD BURNERS ON EBAY.  WHEN YOU SEE A REAL GOOD PRICE FOR A NEW DVD DRIVE THAT IS LISTED AS "OEM" IN THE DESCRIPTION, BE CAREFUL.  I HAVE BOUGHT TWO OR THREE THAT WORKED UNTILL IT WAS TIME TO FLASH THE FIRMWARE TO UPGRADE THE DRIVE.  A LOT OF THESE DRIVES WILL WORK IN MOST COMPUTERS, BUT SOME CANNOT BE UPGRADED IF THEY ARE NOT IN THE COMPUTER THE MFG. INTENDED.  A LOT OF THESE DRIVES ARE IDENTICAL UNITS MADE BY THE SAME COMPANY, BUT CODED IN THE FIRMWARE, SO THEY CAN ONLY BE UPGRADED  IN THE COMPUTER THEY WERE INTENDED FOR.  IF YOU KNOW HOW TO HACK THE FIRMWARE, YOU CAN MAKE THE DRIVE WORK IN YOUR COMPUTER.  MOST PEOPLE DONT THOUGH.  JUST SOME ADVICE FROM MY EXPERIENCE WITH THESE "OEM" DVD DRIVES.