Thanks for your answer. I formerly used 4x speed, but it gave me a lot of I/O errors. When I started using 6x, I was getting them rarer that on 4x and I used 6x since then. About buffer problems, I've been wondering about them as well, I always free as much memory as I can before the write, but they still happen every few writes, it seems to be kinda random. E:\ drive is partition. And about the writer, I noticed that there are 3 versions: 116, 116D, 116DBK. Do you know what are the differences between them and which one is the best for DLs? Thanks in advance.