Serial ATA - Page 1
is the next generation personal computer
(PC) storage interface. It will replace the Ultra ATA/100 interface used to
connect most PCs to their primary storage, which is projected to become a bottleneck
within two years. This paper describes the primary benefit of the Serial ATA
interface, the increase in data rate. Other features and benefits are also outlined,
together with a comparison to alternative storage interfaces.
- The Need for Change
The Advanced Technology Attachment (ATA) interface, previously called Integrated Drive Electronics (IDE), has existed in substantially the same form since 1989, and has become the highest-volume disk drive interface in production. Quantum has led continuous improvements to parallel ATA that extended its data transfer rate from 3.3 Megabytes per second (MB/s) to 100 MB/s, with only one cable change. As PC processor performance has increased, so have the read/write data rates of hard disk drive (HDD) heads and media. This disk rate is projected to exceed today's 100 MB/s interface bandwidth by 2003. Parallel ATA has kept pace in the past, but is nearing its limit, becoming a performance bottleneck. Serial ATA will eliminate this bottleneck by initially offering 150 MB/s and in the future it will provide significant headroom for future improvements.