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General discussion

Harddrives

Jun 24, 2005 12:07AM PDT

I know there are a lot of different types of Hard Drives and I was wondering if there is a good guide that describes the differences between ATA, SATA, P-ATA, etc. that I have seen people and ads mention.

Discussion is locked

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Re: Harddrives
Jul 8, 2005 3:29AM PDT

ATA and P-ATA mean the same.The 'P' was added only to differentiate between regular ATA and the new SATA drives. Physically there is no difference, it's just the connectors are different. Whereas P-ATA use a ribbon cable, S-ATA only needs a narrow cable, so there's less obstruction to airflow inside the PC case which means everything inside it runs cooler.

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Hard drives
Jul 21, 2005 7:29AM PDT

ATA and ATAPI are the real names for the mass storage device interface that is frequently called IDE and EIDE. IDE and EIDE are mostly used by marketing people who do not know what they are selling and by writers for magazines who do not know what they are writing about. IDE was the original interface invented by John Squires (One of the founders of Conner Peripherals, a drive company that was bought by Seagate) IDE stands for Intelligent Drive Electronics, and EIDE is Enhanced Intelligent Drive Electronics. (Enhanced with LBA, or Logical Block Addressing) Before IDE was invented, drives had to have a separate controller similar to the controllers used by SCSI drives these days. Anybody remember the old MFM drives?

What does ATA mean? It stands for AT Attachment but most people don't remember what an AT is anymore (anyone remember the IBM PC/AT?). And what about ATAPI? It stands for ATA Packet Interface.

ATA/ATAPI is the most popular device interface today. Of the approximately 140 million hard disk drives made in the last year, 90+ percent are ATA. The remainder are various types of SCSI inteface drives. And the vast majority of CD-ROM drives are ATAPI devices. Most PCMCIA and CFA mass storage devices are also ATA or ATAPI devices.

SATA is Serial ATA... The old ATA is now referred to as PATA, or Parallel ATA.

Serial ATA or SATA is the newest version of the ATA interface. SATA claims to support all the traditional ATA functions but does it over an interface cable with only 7 wires (instead of the normal 40 wires for traditional parallel ATA interfaces). SATA also claims it will be faster than PATA but the history of serial interfaces indicates you should be careful when reading such speed claims.

Discussing SATA is difficult because: a) SATA was created by a "secret society" that prohibits members from talking outside of their meetings, b) current SATA documents are available only to the members of the "secret society", c) by the time a SATA document is made public it is basically obsolete and has been replaced by a new but secret SATA document, d) the SATA "secret society" is working with the Serial Attached SCSI (SAS) committee(s) to also replace SCSI, e) the SATA documents that are public may be or will be re-published (probably with some changes?) by the T10 and T13 standards committees. (The "secret society" is basically the drive manufacturers)

There is no doubt that SATA is the future. SATA hard disk drives and PCI bus SATA host controllers are shipping today, and their volumes are quickly moving towards the majority. A lot of motherboards shipping today have SATA interfaces. SATA will probably replace traditional parallel ATA within a couple years... Many OEM's have stated that they will be phasing out PATA in the fairly near future...