Dell just replaced my NEC DVD-RW with an Optiarc AD-5540A and I'm having problems burning as well. Mine occurs consistently after 8% is burned. I get a "dirty disk" error. While this might sound like media, I am using the same media I was successfully burning before the drive swap, and I've tried various types of media and get the same error, always at 8%.
I'm contacting Dell tonight and will pass on any info I find. If you come across any answer, please advise.