In the following tests we examine 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 came from ALMEDIO.

- Single Layer media

ABEX TDR-821

This is a single sided, single layer DVD-ROM with 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.

If you have a look at the "Transfer Rate Reading Tests" a few pages back in this review, you will see that in some cases, the E616A drive starts reading a disc at 5x (or even lower), but immediately increases its speed to 7x. This is what happened with the TDR-821 test disc. The disc was read without problems and there were only some speed fluctuations at the end of the reading process.

ABEX TDR-825

This is also a single sided, single layer DVD-ROM of 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 speed fluctuations that were observed with the TDR-821 disc were again present with the TDR-825 disc. Again, no errors were logged during the reading process.

- 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.

In this case, the drive needed to lower its speed a little when the reading the scratches on the second layer. The Auto-Switch control automatically increased the speed once the errors were overcome.

ABEX TDR-845

The disc is a single sided, dual layer DVD-ROM disc with 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 micrometers.

The ASUS reader had no problems reading this disc either.

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 disc checks the layer switch operation from layer 0 to layer 1 and also includes 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.

The drive had some difficulties reading this test disc. Fortunately, no errors were logged, while only the speed was reduced to ensure safe reading.

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 disc's surface, sized from 0.4 to 1.0 mm. It also has 65 - 75 micrometer thickness, fingerprints.

The TDV-545 test disc was no problem for the E616A. It took only 13:58 mins to finish the reading process for both layers, while no speed drops were introduced this time.

An overall good, fast and reliable reader. There were no errors with any of the DVD error correction test discs we used with this drive.