SATA hard drives ....

SERIAL ADVANCED TECHNOLODY ATTACHMENT STANDARD

If we talk in terms of computer hardware, Serial ATA or SATA is a computer bus technology mainly designed for the transfer of data to and from a hard disk. It is the successor to Advanced Technology Attachment standard (ATA). This older technology was renamed as paralle ATA or (PATA) to distinguish it from Serial ATA. Both SATA and PATA drives are IDE (Integrated Drive Electronics) drives, although IDE is often misused to indicate PATA drives.

......... and now .... where everyone of us is confused most of times. what is so special with these sata hard drives.

SATA vs SCSI

SCSI will offer you transfer rates quite higher than SATA hard drives , but yes it is more complex bus and hence a bit costier. Some drive manufacturers also offer longer warranties for SCSI devices, however, indicating a higher manufacturing quality control of SCSI devices compared to PATA/SATA devices. SCSI buses also allow connection of several drives (up to 16 or even 127) whereas SATA only allows one per cable.

SATA 3.0 Gbit/s offers a maximum bandwidth of 300 MB/s per device compared to SCSI with a maximum of 320 MB/s per bus.

SATA 2 devices are generally compatible with SAS enclosures and adapters, while SCSI devices cannot be directly connected to a SAS bus.

SCSI system focus has been mainly on high speed with support for many devices or hard drives in arrays. SATA focus has been more on large storage capacity in a single or dual hard drive application. SAS type SCSI and SATA will likely merge in the near future under a common standard.
Another difference between ATA and SCSI is reliability, SCSI is mostly used in many organizations for server purposes(like web servers, database servers etc etc) where as ATA hard drives are used for PC storage usage. So we dont need to run ATA hard drives throiughout the day or say 24/7 because people shut down their computers from time to time, SCSI harddisks on other hand are used in servers and have to be accessible at any time and any downtown is at high costs, so SCSI has had much engineering in high reliability where ATA has no need for it.

Backward compatibility

The backward compatibility of SATA hard disks is almost meaningless because SATA-native drives feature both power and data connectors that are incompatible with the connectors used by PATA, SCSI, or any other format of hard drive. However, there are converters that attach to a SATA hard disk allowing it to function as a PATA drive. Some drives come with both SATA and molex power connectors. There are also powered enclosures that hold a SATA drive and act as external USB devices, with the restrictions noted above.

New devices on the market enable some backward compatibility . There are small cards that plug into a PATA connection on the motherboard that allow one to connect a SATA drive. PCI
cards with a SATA connector are available that allow SATA drive to connect to legacy systems without SATA connectors.

Despite its backward incompatibility with other interfaces, it is backwards and forwards compatible with itself. Well it means that , you can connect a SATA drive to a SATA controller and you dont have to worry about specifications - they negotiate the speed (Ethernet). Some of the older controllers may not do this job for this and hence you have to do this at your own - by forcing with the help of a jumper.


SATA HARD DRIVES & LINUX


Several problems arise while you try to install linux(almost every distribution) on a computer with sata hard drives. Here is a good tutorial.