Hard disks buyers guide

Connections

To connect hard disks in the computer nowadays most drives use the Serial ATA (SATA) connection. These thin cables connect straight to the controller on the motherboard, and one cable can only connect one drive. Its predecessor, parallel ATA (P-ATA), uses broad flat cables and on one of these cables two devices can be attached. Intel has stopped to support P-ATA connections on their newer motherboards, instead offering 6 or more SATA connections. Furthermore, most modern motherboards have more than enough SATA connections, which is why we only list test results of SATA drives in our database. The P-ATA interface is still used for optical devices like a DVD or CD drive.

Serial ATA comes in two standards, SATA-150 and SATA-300 (also known as SATA-II). As the name implies, the maximum throughput of the latter is higher, but there are other advantages to SATA-II. It is possible to "hot-swap" devices using the SATA-II standard, so you can add or disconnect drives without powering down the computer, making this standard extremely useful for external devices. Although not many external devices use the SATA-II standard at this time, more and more motherboards have an eSATA (external) connection to connect these drives.

At the moment most external drives use USB 2.0, which is available on all newer systems making these devices compatible with almost everything. The big disadvantage of USB 2.0 is the amount of processor power it uses when a device is attached, while FireWire and SATA-300 use a lot less CPU time when connected. This is why we recommend using an external drive with a FireWire connection, if available. Most modern external drives will offer FireWire 400 (IEEE1394a) and FireWire 800 (IEEE1394b), the latter again being faster, but these connection are very rare on motherboards. Some drives will also offer USB on-the-go; this allows you to directly connect to any device using a USB interface, like a digital camera, and exchange data without using a PC.

Making an external drive yourself is not exactly rocket science. If you have a spare drive you can easily turn this into an external one using a purpose made casing obtainable from most hardware vendors. Special external drive series are the Maxtor Onetouch III Turbo edition 1 Terabyte and the LaCie Little Big Disk, which contain two drives and higher transfer speeds as well as larger capacity drives.