Drive time

Rewritable DVD drives are on their way to becoming indispensable tools for PC users. It won't be long until they replace rewritable CD drives.DVD rewritables are hard to beat when it comes to capacity and versatility. They can read, write and rewrite up to 4.7G of information per disk side and will read both DVD-ROM disks and most CDs, so those music CDs you've collected won't be wasted. You can use them to create your own training videos, store hundreds of images and record numerous sound files.How do they compare with CDs?Higher capacity. A read-only DVD-ROM disk can hold up to 17G of data, and rewritable DVD drives can write and store 4.7G of data per disk side; almost eight times the capacity of 650M CD media.Meanwhile, DVD technology will perform all the applications and more that CD technology does'education, entertainment, reference, data retrieval, software distribution and video storage, to name a few.[IMGCAP(1)] Speed. Because DVD drives use laser beams with short wavelengths that create smaller data pits than do CD drives, the data tracks on DVD disks are much more compact. DVD drives not only read data more precisely, they also read faster. A 1x CD-ROM drive has a maximum data rate of 150 Kbps, but a 1x DVD drive transfers data at 1,350 Kbps.Multiple formats. As well as reading and writing to various DVD formats, rewritable DVD drives can read virtually any CD format. Some can also write to CD-R (write once) and CD-RW (write, rewrite) disks.Advanced video and sound. The MPEG-2 video compression standard used by DVD provides video quality that far surpasses that of MPEG-1 and other compression techniques used in CD-ROM and video CDs. This, plus Dolby Digital Surround Sound (AC-3) audio compression will provide up to 133 minutes of high-quality video and audio that can be stored on a single DVD disk and viewed through a TV set or multimedia computer.Double-sided recording. Although CD and DVD disks look alike, they are built differently. CDs come in a single substrate that is 1.2-mm thick; DVD disks use two bonded 0.6-mm substrates. CDs can record only on one side; DVD disks can record on both sides.PC and TV applications. DVD technology was designed for both work and entertainment. Serious PC buffs make use of advanced DVD error-correction, modulation and playback techniques, as well as buffering techniques for copying and storing both sequential and nonsequential data.Gamers and TV users enjoy MPEG-2 compression and Dolby AC-3 audio compression, which let them create full-motion video and play back full-length movies with gorgeous sound and stunning images.[IMGCAP(2)] That's the good news about DVD. The bad news is that the industry is beset by competing standards that result in a confusing alphabet soup of names for different flavors of DVD. This makes it difficult for potential users to pick the drives that will work best for them.Following are descriptions of the most popular rewritable DVD drive types. They all work well, but the type best suited for your purposes is up to you.CD-RW/DVD combo drives. These drives combine the write and rewrite capability of CD-RW with the read-only capability of DVD-ROM. They are popular among buyers already familiar with CD-RW technology and who don't want to install two separate drives but still want the ability to read DVD-ROM disks.Though they don't have the flexibility of other rewritable DVD technologies, one of these drives can be a good buy if you want to stay the DVD course while waiting for something better. Prices of these drives are already competitive and will drop even more as new systems enter the market.Addonics Technologies Inc.'s Portable Combo DVD+CDRW drive is a versatile external system using CardBus PC Card, FireWire and Universal Serial Bus interfaces. It supports notebook or desktop PCs running Microsoft Windows 98, 2000, Me and XP and comes with CD mastering and PowerDVD MPEG-2 software.LG Electronics USA Inc.'s DVD and CDRW Combo Drive is designed for internal Enhanced IDE and AT attachment packet interface installations.Plextor Corp.'s PleXCombo series incorporates either internal ATAPI or external USB interfaces.DVD-RW drives. DVD-RW (DVD-Rerecord) is a rewritable format that lets users record, erase and rerecord their own DVD disks up to 1,000 times. These drives can also write to CD-R/RW media and can read practically all types of CD disks.The idea behind this format, which is supported by the DVD Forum, is to provide a means for users to record DVDs that are easily compatible with existing DVD video players and DVD-ROM drives. DVD-RWs contain up to 4.7G of information per side and can be used to store video, audio and other types of data.The latest DVD-RW drives, such as Hewlett-Packard Co.'s Compaq 4.7GB DVD-RW R4 Carbon and Pioneer North America Inc.'s DVR-AO4 also include DVD-R (write-once) capability. DVD-R provides a sequential write with no overwrite capability and is used for disk premastering.DVD-RAM drives. The DVD-RAM standard, backed by Hitachi America Ltd., Panasonic Personal Computer Co. and Toshiba America Information Systems Inc., allows more than 100,000 rewrites to disk.Its proponents say the technology is compatible with the widest possible range of available DVD drives, including DVD-ROM and DVD-R. A DVD-RAM drive can also read CD-ROM, CD-R/RW, Video CD, CD-Extra and Photo CD disks. Disks written by DVD-RAM drives can store up to 9.4G of data.[IMGCAP(3)] Panasonic's LF-D321U is a Windows-compatible internal EIDE/ATAPI DVD-RAM/R unit with a good supply of supporting software. Pacific Digital Corp.'s DVD Burner is a similar unit with DVD camcorder software support and Hitachi America Ltd.'s GF-2000 and GF-2050 are also Windows-based drives, but they aren't aimed at end users.DVD+RW+R drives. DVD+RW is the latest proposed DVD standard and is supported by industry giants such as Dell Computer Corp., Hewlett-Packard, Philips Electronics North America Corp., Sony Electronics Inc. and others. More than 25 other companies have joined the DVD+RW Alliance to pledge support for DVD+RW and its companion standard, DVD+R. Other drive and disk manufacturers are expected to follow as the standard builds momentum.Its proponents claim that DVD+RW offers two-way compatibility between computer platforms and consumer electronic devices. It supports real-time video recording and random data recording and reportedly offers full compatibility with existing DVD-video players and DVD-ROM drives.DVD+RW offers unlimited rewrites of up to 9.4G of data on double-sided disks, and the drives can also write to CD-RW media. As with other DVD standards, DVD+RW is backwards-compatible with virtually all CD formats.DVD+R adds write-once capability to the mix and requires the use of slightly different media for tamper-proof data mastering. New drives, such as AOpen America Inc.'s DVRW2412Pro and Hewlett-Packard's Windows dvd200i/e series with IDE or external USB and FireWire interfaces come with DVD+R capability. Sony's DVD+RW/CD-RW recorder internal model DRU120A is another example.