The LG GSA-H22N is a Super Multi DVD Rewriter, meaning that is fully supports reading and writing the DVD-RAM format.
DVD-RAM is a veteran among the three DVD formats. It is a ten-year old format, and it predates the DVD-R format by one year.
LG’s Super Multi drives have played a significant role in spreading the use of the DVD-RAM format from camcorders and standalone devices to computers, by combining DVD-RAM support with DVD+R and DVD-R support, thus making DVD-RAM use possible without having a separate drive.
The DVD-RAM format is inherently more reliable than other DVD rewritable formats due to its superior error control, defect management, and the option of hardware-based data verification during writing.
DVD-RAM defect management provides data structures, stored on each disc, that allow unusable sectors to be relocated. It also allows the number of relocated sectors to grow over time, effectively reversing the negative effect of gradual media deterioration.
While DVD+R and DVD-R data track is spiral, DVD-RAM track layout is concentric, similar to that of a hard drive platter.
Looking at the recording side of a DVD-RAM disc, it is easy to notice that the data surface is very different from DVD+R and DVD-R discs. It has a fascinating pattern of small rectangles:
A DVD-RAM disc can be formatted in any of the following formats: FAT32, UDF 1.02, UDF 1.50, UDF 2.00, UDF 2.01, and UDF 2.50.
Many operating systems (Mac OS X, Windows XP, Windows Vista) support DVD-RAM formatting, reading and writing directly, without the need to install any additional drivers or software. Once a DVD-RAM disc is formatted, it acts like a removable hard drive and all writing is done in the background. This means that you do not have to wait for the drive to finish writing and can continue working with applications while the DVD-RAM drive is doing the burning.
Lets us take a look how the LG GSA-H22N works with DVD-RAM:
Maxell 12x DVD-RAM media, manufactured by Maxell
(Thanks to ExtremeMhz for providing this media)
Writing Maxell 12x DVD-RAM without verification
Writing Maxell 12x DVD-RAM with verification
Reading Maxell 12x DVD-RAM (transfer rate test)
As we can see, the LG GSA-H22N writes 12x DVD-RAM in 5 minutes and 42 seconds without verification, and reads back at 12x speed in 5 minutes and 34 seconds.
With verification, writing a full 4.27 GB DVD-RAM disc takes 14 minutes and 36 seconds.
Please note how turning on data verification has slowed writing speed from an average of 10.11x to 3.88x. This is due to the drive constantly reading back the data after writing it, to verify that it has been correctly stored. It is a slow writing technique but in combination with the defect management mechanism of DVD-RAM it is as close to "bullet proof", in terms of preventing data loss, as one can get with optical media.
Maxell5x DVD-RAM media, manufactured by Maxell
(Thanks to Maxell USA for providing this media)
Writing Maxell 5x DVD-RAM
Reading Maxell 5x DVD-RAM
As we can see, the LG GSA-H22N reads and writes a full 4.27 GB 5x DVD-RAM disc in approximately 12 minutes.