Hitachi GF-1050 DVD-RAM Drive

The promise of DVD-RAM has kept many from making that move to DVD-ROM — why fork out for a DVD-ROM drive,
when the superior DVD-RAM technology is Just around the comer? DVD-RAM offers one key capability that DVD-ROM lacks: writability. Not just once, like CD-R or DVD-R, but random access rewritability, so the drive can act like a floppy disk, but with several thousand times the capacity.
It is meant to be the holy grail of removable storage, and not just for computers either — it has frequently been touted as the technology that will kill VHS and other tape media, simply by virtue of its massive capacity and random access capabilities. In japan recently, Panasonic, another vendor that will soon be releasing a DVD-RAM drive, demonstrated DVD applications which could revolutionise the video editing market by using the random access capabilities of DVD-RAM. Systems backup could also be capably handled by DVD-RAM, as could software distribution. The potential of DVD as a storage medium is immense, but does the reality match the hype?
In an exclusive preview, APC took a look at the first DVD-RAM drive that will hit the market in Australia — Hitachi’s GF-1050 — and tested it to see whether it lived up to expectations.
The standards split
Unfortunately for consumers, there has been some confusion over DVD-RAM which will inevitably slow its uptake. The confusion arose over a split between some of the vendors involved in the production of DVD-RAM equipment. Last year, a number of vendors, notably Sony, Philips, NEC and Hewlett-Packard, decided not to go along with the DVD Forum’s specifications on DVD-RAM, choosing instead to implement their own standards, which were fundamentally incompatible with DVD-RAM.
Instead of the DVD Forum’s proposed 2.6G-per-side capacity, Sony, Philips and HP are pursuing disks with capacities of 3G per side, while NEC seeks a 5.2G-per-side capacity. The technologies that will be used to store data on these disks are incompatible with each other, to the extent that DVD-RAM disks from any one camp won’t be able to be read on systems from others. The devices produced by Sony, Philips, HP and NEC are expected, however, to be able to read DVD-ROM disks.
In response to this split, the DVD-Forum rapidly began working on a new standard, enabling 4.7G per side, which would bring DVD-RAM capacities in line with single-layer DVD-ROM capacities. This move prompted NEC back into the fold of the DVD-Forum, but the other vendors are still pursuing their own technologies, although Sony remains a member of the DVD Forum.
The Hitachi GF-1050 we looked at meets the original DVD-Forum specification, with maximum capacities of 2.6G per side — very much a first-generation product. It will not be able to read or write 4.7G disks when they become available. In a sense, it has already been superseded by
this second-generation specification, but devices based on the latter will not be available for some time yet.
How it works
The DVD Forum’s DVD-RAM standard is really an evolution of Panasonic’s Phasechange Dual (PD) technology, which is already widely available as a rewritable CD-ROM standard.
PD and DVD-RAM disks use high-intensity laser pulses to generate bits by altering the crystalline structure of the media. This bit either absorbs or reflects light when a read operation is called for. The recording material can be returned to its original state via a medium-intensity laser which reverts the structure to its initial non-amorphous state, ready for further write operations.
DVD-RAM enables, as the name implies, random access during both read and write operations. This means you can drag and drop individual files to and from the disk as you would a hard or floppy disk. You do not have to make ‘images’ as you do with most CD-R media. Interestingly, Sony, HP and Philips are looking at technologies slightly different to PD for their products. These vendors ore looking to evolve the technology used in CD-RW (CD rewritable) for use in their products (which are likely to be called DVD-RW drives).
To provide the kind of reliability to read and write DVD-RAM, a cartridge format is required. Essentially, sealed DVD-RAM cartridges look rather like overlarge versions of the 3.5in disk, sliding window and all. Technically, a sealed DVD-RAM cartridge is only required to protect doublesided disks, while single-sided disks can be placed in and removed from cartridges, much like early CD-ROMs were placed in caddies for insertion into drives. Non-car-tridge media, such as DVD-ROMs and CD-ROMs, are inserted into a depression in the bottom of the tray in which the RAM disk is normally inserted.
As we’ve noted, the Hitachi GF-1050 has a capacity of 2.6G per side. In the case of this product, switching between sides requires actively removing the cartridge and turning it over, although Hitachi representatives said that they did not expect it would be too long before we see devices which can read from both sides of the disk without needing to remove it from the drive.
Compatibility
The list of backward compatibilities of the Hitachi DVD-RAM drive is impressive. Pretty much any flavour of CD media can be read by the drive, including CD-ROM, CD-R, CD-RW and CD-Audio (and the drive also includes a headphone jack and volume control at the front for the latter). It can also read several types of DVD disk, including DVD-RAM (of course), DVD-ROM and the rare DVD-R media. It cannot read Divx media.
While the GF-1050 APC looked at was a standard SCSI-11 device and fitted inside a typical internal 5.25in drive bay, Hitachi will also be offering an EIDE version of the device (the GF-1000) as well as an external SCSI DVD-RAM drive (the GF-1055). It is set up in the BIOS as a standard removable media device.
Performance
In our preliminary testing, the Hitachi GF-1050 proved adequate at reading data from the supplied DVD-RAM disk, although it did not perform nearly as speedily when it came to write operations. However, the device we tested was a hand-built pre-production sample, and the results may not fully reflect the scores that a shipping device would achieve. The SCSI controller used was an Adaptec 2940.
The official figures for the device are relatively impressive. According to Hitachi, the GF-1050 can read DVD-ROMs at the same speed as normal second-generation drives — 2x, or 2.76M per second, while it can read and write DVD-RAM disks at DVD-ROM lx speed, or 1.38M per second. It was also listed at being able to read CD-ROM media at 8x maximum (1.2M per second). The rated average access time was 200ms for DVD-RAM/ROM disks and 120ms for CD-ROMs.
When it came to read operations on all types of media, our test results bore out those specifications, although write times for DVD-RAM media were somewhat disappointing.
The first benchmarks we ran tested the streaming performance of the drive. We timed large file transfers to and from the GF-1050 to get an indication of the streaming performance of the DVD-RAM media.
Copying the file from the DVD-RAM to the EIDE Mode-4 hard disk took one minute and four seconds, which averages out to about 1.27M per second — pretty much in line with the rated speed of the drive, and certainly enough to play any MPEG-2 movies stored on the disk.
Writing to DVD proved to be a challenge for the DVD-RAM drive. When we copied the same file from the hard disk to the DVD-RAM disk in order to test its write speed, the drive took a painstaking nine minutes and 23 seconds. This means it transferred data at a measly 145K per second — enough for CD audio but nowhere near enough for MPEG-2 video of any quality.
What does this mean? It means that the dream of a ‘VHS replacement’ is certainly not going to happen with this generation of drives. If you want to record movies in real time to a DVD-RAM disk, it will essentially require that the movie be saved to the hard disk while being recorded, and then copied across to the DVD-RAM disk (and copying 3G+ at a rate of about 150K per second is not going to appeal to a lot of people: it would take about six times the length of an MPEG-2 encoded movie). In a consumer device, this is certainly unacceptable, and those few who have touted DVD-RAM as hard-disk replacement technology have definitely got it all wrong; if anything, this first generation of DVD-RAM will increase demand for hard disk capacity, not reduce it. On the subject of hard disk replacements, we also tried to run Ziff-Davis’ WinBench Disk WinMark hard disk benchmarking software on the drive, but the GF-1050 failed to complete the tests within a reasonable amount of time. Obviously, the drive is not well suited to the series of small reads and writes that Disk WinBench calls for, and is far better used for streaming applications and large file transfers.
We did manage to run CD-ROM WinBench on the drive, which tested the speed at which the drive could read from CD-ROM media, and in this case the GF-1050 performed admirably. With its 8x CD-ROM rating, the GF-1050 scored 749K per second in the benchmark. By comparison, a Hitachi DVD-ROM drive, with its 20x CD-ROM rating, scored 996K per second using the same benchmark.
The cost
The GF-1050 is certainly not a purchase for the cash-strapped consumer at this stage, costing in the region of $1,580 for the drive itself. This drive does not come with any kind of MPEG-2 decompressor, although several vendors may come out with kits once the product has started shipping.
While the drive may be expensive, the media itself offers unrivalled capacity for the price. You should expect to pay about $50 for a single-sided (2.6G) disk or $80 for a double (5.2G). This translates to about 1.5 to 2 cents per megabyte — far, far less than any other rewritable removable media solution on the market.
DVD-RAM should prove to be an outstanding archival and data sharing medium, but its slow write performance at this early stage limits its usefulness somewhat. In spite of this, Hitachi’s DVD-RAM is an excellent product for removable data storage, and its high asking price is more than offset by the extremely low cost of the media.