SATA vs PATA Hard Disk Drives: A Guide

With the advent of new SATA drives, as you probably know, there was a big naming issue. The old IDE drives needed a name to distinguish it from SATA drives and so the name PATA was born. The P in PATA refers to Parallel (ATA drives) while the S in SATA is Serial (ATA drives). More elaborately, SATA stands for Serial Advanced Technology Attachment and PATA stands for Parallel Advanced Technology Attachment. PATA and SATA drives don’t just differ in name, they differ significantly in functionality too. Here are the gory details for your reading pleasure:

Comparison between PATA drive and SATA drive

• SATA is capable of data burst rate of upto 150 MB/s whereas PATA can deliver only upto 133 MB/s speed. The latest SATA II technology can have burst rate upto 300 MB/s. SATA has sustained throughput of around 55 MB/s while it is 52 MB/s data transfer rate rate for PATA drives. So, there is about 5% increase in efficiency in sustained throuput.
• SATA cables have only four wires two for sending and two for receiving data. On the other hand, PATA cables have 40 pins with 20 pins at a row. PATA cables come in 40-wire or 80-wire designs. Most modern storage devices require the use of the more capable 80-wire PATA cable to meet certain speed requirements. PATA cables are bulky, hard to install and impede air-flow in the chasis. SATA cables are easier to install & uninstall, consume minimal space and do not impede the air-flow thereby allowing better circulation.
• The connect pin height for SATA are designed so that ground pins connects first while connecting the cable and when disconnecting, the ground pins are removed last. As such SATA hard disk can be removed even in running condition without any damage to the disks.
• SATA supports hot plug facility which was previously available only on SCSI & SAS devices
• Both support similar speed and also cost nearly the same. In fact today you may find PATA drives costlier because if low availability.
• SATA use low voltage differential signaling method that allows higher transmission speeds on longer cables. So the cable length may be upto 1 mtr long. PATA cables can be upto a maximum of 45cm.
• The connect pins are more robust and hence durable in PATA. There is a risk of bending the pins in the motherboard connector for SATA.
• The power connectors for SATA and PATA are also different. It is simpler (and less painful on the hand) to connect SATA power cables.
• SATA has reduced risk of electro-magnetic interference from other components in a system.
• SATA drives do not need to use jumper settings for master or slave configurations. In fact SATA drive has eliminated the concept of master-slace configurations. You simply use a different connection for each drive. The simplicity means ease of installation too.
• SATA enables lower cost but higher density hard drives unlike PATA. Today we have terabyte SATA drives available at commodity prices, something we couldn’t even imagine for PATA drives.

Overall SATA drives are significantly superior to PATA drives. If your Motherboard / Mainboard supports SATA as well as PATA drives then always go for SATA drives. The only reason you should buy PATA drives today is for legacy system and then you should stock them now because very soon they may not even be available.