Mechanical Design Factors

The defining performance-limiting characteristic of hard disks compared to the other main "performance" components is the fact that they operate mechanically. Consider the other components of the PC that have a fundamental impact on overall system performance: processors, motherboards, system memory, video cards. They are all solid-state--no moving parts--and as such much faster than the mechanical parts that make up hard disks. That's why memory access times are in nanoseconds, for example, while hard disk access times are in milliseconds--a million times slower!

Since mechanical parts are largely what limit hard disk performance, that makes them the most important factors affecting performance. This section takes a look at three of these key mechanical design factors in more detail.

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