PC Hardware in a Nutshell, 3rd Edition

DVD+RW

Originally called DVD+RW, changed to +RW when the DVD Forum objected, and later changed back, DVD+RW is backed by Hewlett-Packard, Mitsubishi Chemical, Philips, Ricoh, Sony, Thomson Multimedia, and Yamaha. Although all are members of the DVD Forum, the DVD+RW standard is not recognized by that organization. First-generation DVD+RW drives were to use phase-change rewritable technology to store 2.8 GB per side. DVD+RW manufacturers formally abandoned the 2.8 GB DVD+RW 1.0 standard in late 1999, without ever having produced drives in commercial numbers. Second-generation DVD+RW drives, which finally shipped in volume in late 2001, expand capacity to 4.7 GB per side and support writing CD-R and CD-RW discs. DVD+RW discs are readable by most recent DVD players and DVD-ROM drives, although as with DVD-RW the lower reflectivity of DVD+RW discs causes some devices to mistake them for dual-layer DVD-ROM discs and therefore refuse to read them. A firmware update solves that problem in many drives and players that experience it. Roughly 65% of older DVD-ROM drives and DVD players can read DVD+RW discs.

DVD+RW backers claim two primary advantages for DVD+RW relative to DVD-RAM. First, like CDs, DVD+RW discs do not use a cartridge (although non-cartridge DVD-RAM discs are now available). This translates into lower costs for drives and media, and allows DVD+RW discs to physically fit standard drives. It also makes DVD+RW drives a viable alternative for laptop systems, which cartridge-based ...