Hard Disk Performance Specifications

Hard disks are often compared by contrasting their specifications. This is a valid way of attempting to discern whether one hard disk is better than another, though due to the large number of specifications often provided, this can also be somewhat difficult to do while being sure to cover all the bases and perform the analysis in a balanced way. It helps to focus on the more important specifications, of course. Certainly, understanding hard disk specifications is essential to understanding hard disk performance.

Structuring a discussion of performance specifications and performance factors in a way that covers all the issues in a way that's not too confusing isn't easy. After (excessive) deliberation, I decided to create two separate sections, one covering specs and the other discussing factors. The difference between them, as I see it, is that a specification is a number or label that expresses an element of performance; a factor is something that causes performance, and hence a specification, to be affected. So specifications are indirectly derived from, and are a result of, the various design factors used to create a drive. A single specification can be affected by a number of different performance factors; and a single performance factor can influence a number of specifications.

Due to this "many-to-one and one-to-many" relationship between these two concepts, there is some overlap between the "specifications" and "factors" sections--there are headings and topics that are the same in both places. In this section, I am focused primarily on what the specifications are and what they represent, how to interpret them and what their importance is. I then relate each of these to the performance factors that influence them, and talk more about the direct impact on performance in the internal performance factors and external performance factors sections. I apologize in advance for any confusion this may cause!

Note: I attempt in this area to be as comprehensive as practical in covering the most important and common hard disk specifications, but at the same time not overwhelm you with every single specification that exists on hard disks. You can find many more specifications in the product manual of a hard disk family, usually available free on the manufacturer's web site.

Next: General Notes On Performance Specifications