In the following tests we examined the DVD reading capabilities of the drive with scratched / defective DVD media. For the tests we used CDVD Benchmark and Nero CDSpeed. The reference test media comes from ALMEDIO.

- Single Layer media

ABEX TDR-821

This is a single sided, single layer DVD-ROM with a 4.7GB capacity and its surface has an artificial scratch of dimensions varying from 0.4 to 3.0 mm.

The following transfer rate picture comes from the CDVD Benchmark v1.21 transfer rate test.

What we have here is an error free test, while the drive managed to reach a speed of 16X at end of the test.

ABEX TDR-825

This is also a single sided, single layer DVD-ROM of a 4.7GB capacity. The data structure of the disc is exactly the same as that of the TDR-821, with the difference that there are no scratches on it but instead defective areas of dimensions ranging from 0.5 to 1.1 mm.

There are also fingerprints sized between 65 and 75 micrometers.

The drive read the first defective area successfully without any significant drop in speed, while towards the end of the second defective area, it dropped its reading speed in order to succesfully read the disc's contents. Once it cleared the defective region, the speed then went back up to 16X.

- Dual Layer media

ABEX TDR-841

This is an 8.5GB dual layer, single sided DVD-ROM disc with artificial scratches of dimensions ranging from 0.4 to 3.0mm, on both layers.

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Excellent performance in this case, notice the smoothness in the reading lines with no major fluctuations in reading speed.

ABEX TDR-845

The disc is a single sided, dual layer DVD-ROM disc of a capacity of 8.5GB. The only difference between the TDR-845 and the TDR-841 is that the first includes defective areas and fingerprints.

The dimensions of the defective areas range from 0.5 to 1.1 mm and the fingerprints are sized from 65 to 75 micro meters.

The ASUS drive slowed its reading speed when reading over the fingerprint defects in Layer0 but didn't slow down when reading the corresponding area in Layer 1. This is the same behaviour as we had seen with the previous ASUS DRW-1604P model.

ABEX TDV-541

The TDV-541 is a single sided, dual layer DVD-VIDEO disc, with a capacity of 8.5GB.The disc is based upon the TDV-540 series which is designed for inspection and adjustment of DVD-VIDEO players. The discs check the layer switch operation from layer 0 to layer 1 and also include test pictures and test signals for DVD sound files.

The current TDV-541 also checks the error correcting capabilities of the drive and includes scratches from 0.4 to 3.0 mm.

While the drive completed the first layer without any errors, in the second layer, in order to succesfully read the whole disc, it dropped it's reading speed. Nevertheless, the reading of the defective disc was successfull. Again, we should mention that the previous DRW-1604P model also had problems with the second layer and in fact was unable to complete the test.

ABEX TDV-545

The TDV-545 disc is based on the TDV-540 series. It is a single sided, dual layer DVD-VIDEO disc with a capacity of 8.5GB.

The TDV-545 includes artificial black dots on the data surface, sized from 0.4 to 1.0 mm. It has also 65 - 75 micro meter fingerprints.

Could have been an excellent reading, if not for the drop in speed near the layer change in the first layer. Eventually, reading was completed succesfully.