Let’s raise the speed up a little and see what happens.

 
Burn quality of the DVD+R discs at 8x

So, here’s why the ASUS SDRW-0804P-D is slower than desktop drives at burning discs: like with CD-Rs, it uses a four-step Z-CLV algorithm instead of P-CAV or two-step Z-CLV. This leads to the drive’s being 4-5 minutes slower than desktop models at burning discs at 8x speed. Otherwise, the burn operation was completed successfully.

The quality of the resulting disc is quite right. The average PI error rate is below 5, which is an excellent result. The total number of PI error blocks (14,404) confirms the highest quality of the disc, too. The peaks of PI failures don’t exceed 3; the average PI failure rate is 2. The total of PI failures is small (771), too.

 
Beta/Jitter (left) and TA Test - Outer (right)

Like in the previous case, there are steps in the Beta graph after which the drive was accelerating its speed. So, the overall shape of the graph is somewhat uneven. The same can be said about the Jitter rate. The drive is constantly adjusting the laser power which immediately affects the shape of the graphs, but doesn’t influence the quality of the resulting disc.

The TA Test shows the drive’s ability to maintain necessary pit and land lengths. The adjacent sections overlap on the diagram, but not too much. The Peak Shift value isn’t as high as to affect the quality of the disc.

Thus, the ASUS SDRW-0804P-D handles DVD+R media well at both 4x and 8x speeds. Let’s see how it burns dual-layer media.

 
Burn quality of the DVD+R DL discs at 2.4x

The burn operation was completed without problems – no slowdowns on the graph. Although the software identified the employed burn algorithm as CAV, the graph clearly shows that it is a classic CLV. You can also see the moments when Running OPC technology starts to work.

The quality of the first layer of the resulting disc is rather average. The average PI error rate is very close to the maximum limit. There are also rather lengthy surges of PI failures above the acceptable limit. The situation improves on the second layer, though, where the errors fit into the norm.

 
Beta/Jitter (top) and TA Test (Outer, layers 0 and 1)

The Beta graph reflects the drive’s incessant adjustment of the laser power and is jagged as a result. The Jitter rate is not uniform along the disc, either. The drive doesn’t seem to have found the optimal laser power and this affected the quality of the resulting disc negatively. As for the correct lengths of pits and lands, the adjacent areas do overlap on the diagrams for both first and second layers. The Peak Shift value is high, too. It means the average length of both pits and lands differs from the reference.