DVD-RAM writing performance:

The Optiarc AD-7240S is a so-called Multi drive, meaning that it also supports the DVD-RAM format. This drive is one of few drives that also supports the DVD-RAM format. Let us look at the recording side of the disc, and as you can see it has differences from the other DVD+R/W/R9 DL and DVD-R/W discs.

We can see a very fascinating pattern of darker spots. These tick marks are “address information” (“Pre-mastered Pit Header Field”) which are embedded onto the disc. This is header information in front of data sector area, and is the same format as HDD and MO. A DVD-RAM disc can be formatted in the following formats:

• FAT32
• UDF 1.02
• UDF 1.50
• UDF 2.00
• UDF 2.01
• UDF 2.50

By formatting a DVD-RAM disc with FAT32 it will act like a removable hard drive and all writing will be done as “background processes”. Meaning you do not have to wait for it to finish, you can start or work with other applications while the DVD-RAM is working without noticing any “hangs” or CPU slowdowns. DVD-RAM has error correction, but also has error replacement to spare sectors as a “defect management” function. This gives higher reliability than other DVD formats. Another advantage with DVD-RAM is that the discs can be formatted/erased/written at over 100,000 times before it will/can cause/report any errors. While the drive is supposed to write and read DVD-RAM at 12x speed, this kind of media is not available in Europe. So we had to limit our tests to using 5x speed media. Lets us take a look at the disc we are going to use in these tests.

Verbatim 5x rated DVD-RAM media

As we can see, the Optiarc AD-7240S wrote our 5x DVD-RAM media with an average 4.85x in 11 minutes and 29 seconds which is what we expected on this media. Now let’s see if the AD-7240S can read our test disc.

The Optiarc AD-7240S had no problems in reading our test disc at 5x. We then ran CD-Speed’s Scandisc function to check the disc for errors.

As we can see, the disc has no errors. In our forum we had reports about some Optiarc drives being unreliable when reading DVD-RAM media. These drives occasionally read wrong data without indicating an error. In order to test this, we wrote a file of almost 4GB in size to the disc and followed this by 6 binary comparisons of the file, but have not encountered a single bit error. However the written disc had a decent quality as you can see from the following scan with the Optiarc AD-7240S itself and the corrupted data that was reported could also be caused by bad discs but this has yet to be confirmed.

Summary:

There were no problems to report with DVD-RAM on our tested media. Now let’s head to the special features page where we will run some advanced tests

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