Burn quality of the DVD-R discs at 4x

Like when burning the DVD+R at 4x speed, the ASUS drive again uses Z-CLV. Yes, this is a two-step Z-CLV algorithm with a very short first step, so the whole burning operation is not greatly slowed, but it is still Z-CLV. Why could the manufacturer choose this algorithm? Maybe because the drive needs more time to choose the optimal burn strategy and to adjust the laser power appropriately.

Unfortunately, the quality of the resulting disc is worse than that of the DVD+R. Yes, the average rates of PI errors and failures are quite acceptable and even low, but the drive burns DVD+R discs better, that’s a fact. By the way, an increase in PI errors can be seen right after the drive reached 4x burn speed, so the drive’s being “cautious” doesn’t help here.

Well, the problem may be in the manufacturers’ paying less attention to optimizing burn strategies for the minimal speeds.

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

The Beta graph again shows that the drive is always in search of the optimal laser power. The graph isn’t straight even in the CLV area. The same goes for the Jitter rate: it changes each time the laser is recalibrated. It seems like the manufacturer left the DVD-R 4x burn strategy in the drive’s hands entirely and the device itself is trying to find a way to burn such discs better. It maintains the necessary lengths of pits and lands well, though (Jitter is minimal). The rather big Peak Shift value spoils this bright picture somewhat, yet overall the results are highly satisfactory. Let’s see what we have at a higher speed.

 
Burn quality of the DVD-R discs at 8x

The SDRW-0804P-D shows its conservatism once again. Its four-step Z-CLV algorithm slows it down considerably in comparison with “desktop” devices. Yes, speed is not the main priority for a notebook drive, but I think users would want to know why their device takes much more time than other drives to burn a disc, the speed formulas being identical. Apart from the employed burn algorithm, the burn operation proper was performed without problems.

The resulting disc is very good. The rate of PI errors and failures is normal (the PI failure rate approaches the allowable maximum on the outermost tracks only). But if we compare this to the quality check of the DVD+R recorded at 8x, we will have to acknowledge a worsening of the results. So I should say it again: the SDRW-0804P-D burns write-once media of the “plus” format somewhat better than discs of the competing format.

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

The Beta/Jitter graphs again show that the laser power is constantly being adjusted throughout the burn session. The Beta graph stabilizes after the one third of the disc and becomes more like a horizontal line, while the Jitter rate is always changing. On the other hand, the results of the TA Test suggest that the drive maintains the required lengths of pits and lands well enough (the Jitter and Peak Shift parameters are both low).

Summarizing the results of the tests with write-once DVD media, I must acknowledge that the ASUS SDRW-0804P-D burns DVD+R and -R discs very well, but DVD+R discs it produces are somewhat better quality than DVD-R. It seems the manufacturer focused more on developing burn strategies for the +R format in the first place.

As for dual-layer DVD+R discs, the drive doesn’t burn them well. Even though the parameters of the resulting disc are within the acceptable ranges, there’s still much space left for improvement.