Features that only one vendor lists: For internal drives and some external drives, manufacturers often make up terms to describe a function or explain what's happening inside the drive. For example, "no-touch ramp load technology" is just a fancy way of saying "vibration reduction," while "IntelliSeek" is marketing speak for "variable RPM." It's not that these functions don't matter, but much of it boils down to promotional copy rather than unique features that give the hardware a competitive performance edge. Chances are, another drive on the shelf does something similar, but calls the function by a different name--or doesn't even draw attention to it at all. Related:

Revolutions per minute (beyond 7200): Many of today's hard drives don't specify a number for revolutions per minute, but it still matters. The physics of speed remain the same, and a 10,000-rpm drive remains faster than a 7200-rpm drive, which remains faster than a 5400-rpm drive. But for all intents and purposes, speed is not a huge competitive focus right now.

Among makers of consumer hard drives, Western Digital is the only one with a 10,000-rpm drive, and that model remains a niche product. Most desktop drives--with the exception of performance-oriented drives--have a variable speed that hops between 5400 and 7200 rpm, depending on the task. Portable drives are where you will likely see the most difference, as in that category it's a big jump between 5400 and 7200 rpm. Even so, you rarely see 7200-rpm external portable drives--and if you do, you'll pay a premium for one. Related: