In the last post we looked at a simple rule that you can use when buying a hard drive for your computer. In this post I am going to look at some of the more technical details to be considered when buying a hard drive.

Interface type

First thing to know is that in the home PC world there is basically two types of hard drive interfaces that we need to be concerned with, SCSI and ATA. The ATA standard has also recently been separated further into Parallel ATA (PATA) and Serial ATA (SATA) with SATA being the interface being used by the majority of recent drives.  SCSI is more often used in professional systems that demand fast and stable data access and is probably overkill for a home system. I would suggest going for a  hard drive that uses a SATA interface which is supported by the majority of the newer drives on the market. However you do need to make sure your motherboard has the necessary controllers  (Most modern motherboards will).

Capacity

The other things to think about are disk capacity and speed. As most people know the capacity of a hard drive is usually measured in Gigabytes although soon it may be Terabytes!  As we mentioned in the last post the size of the drive you need will be determined by what you want to do with your computer but as a rule of thumb you should buy the biggest drive you can afford. I would recommend at least a 500 GB or 750 GB drive.
Speed and Cache

A disk’s data access speed is a function of the rotation speed of the disk inside the hard drive and the amount of memory cache included with the drive. The rotation speed is measured in RPMs  (Rotations per Minute). The faster the drive rotates, the more quickly data can be written to and read from, the hard drive.  I would generally recommend buying a 7200 RPM drive. A drive’s memory cache helps to speed up the accessing of the information on the drive and the more of it the better. Drives with a higher capacity will have often have 32 MB or more of cache which would be my recommendation.

A good choice might be the Seagate Barracuda 7200.11 - Hard drive which is  a 750 GB, 7200 RPM drive with a 32 MB cache.