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Quick-formatting hard disk drives: A shortcut, but safe

Quick-formatting a new hard drive takes only seconds, but simply erases the drive's metadata and file allocation tables. Full-formatting, which can take several hours, goes sector-by-sector across the disk, erases it and tests it for possible read errors. For the most part, there's no harm in quick-formatting. Enterprise-class drives (or consumer-level drives with three-year warranties) have already undergone error testing to ensure they will hold up.

The first thing most people do with a new, out-of-the-box hard disk drive is, of course, format it. But they have a choice: They can either format a hard disk drive the "quick" way or opt to format it the "full" way.

Quick formatting, which only takes a few seconds, simply erases the hard disk drive's metadata and file allocation tables. Full formatting goes sector-by-sector across the disk, erases it and tests it for possible read errors. This method, a holdover from the days when many hard disk drives would arrive from the factory almost guaranteed to have defects of some kind, can take several hours.

Because of the amount of time involved in full-formatting a hard disk drive, most people are loathe to do it; they'd rather quick-format and get to work using the drive right away. Yet at the same time, they're also worried that if they quick-format, they run the risk of potential disk errors in the future.

Okay to quick-format hard disk drives?
For the most part, there's no harm in quick formatting. If you buy an enterprise-class drive, or a consumer-level drive that has a three-year warranty, the drive has already undergone a certain amount of error testing to ensure that it will hold up. This is why enterprise-class and "Pro" desktop hard disk drives cost that much more: the more expensive the drive, odds are there's been that much extra quality control checking performed on it.

Enterprise-class drive hardware and (to a lesser extent) desktop drives also have native hard error correction that traps bad sectors and relocates data from them whenever possible. For instance, RAID arrays typically scan for errors when rebuilding a hard disk drive in a mirror set, and many arrays scan passively for errors during periods of low disk activity.

Over the past 10 years, I have used (and retired) at least 10 different "Pro" desktop hard disk drives of various makes, models and sizes. Each one was quick-formatted, and the only drive failures I ever experienced were for reasons that had nothing to do with a physical error on the surface of the drive. If you feel more reassured by performing a surface test when formatting, go ahead and do one. But it's not as crucial now as it was a decade ago.

Note:There is a major exception when using quick format to format a hard disk drive: This exception applies when you're preparing to retire a hard disk drive from service, and you don't want any possibility of the data on it being compromised. A quick format will only erase the volume's header data and file allocation tables, but won't erase the files themselves. If you want to be absolutely sure the drive is wiped, use a product like Eraser or Darik's Boot and Nuke to systematically wipe all the data on the hard disk drive.

About the author:
Serdar Yegulalp is editor of the Windows Power Users Newsletter, which is devoted to hints, tips, tricks, news and goodies for Windows NT, Windows 2000 and Windows XP users and administrators. He has more than 10 years of Windows experience under his belt, and contributes regularly to and

Hard disk drive management technical guide

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  Storage management software helps when hard disk drives fail
  Quick-formatting hard disk drives: A shortcut, but safe
  Erasing hard disk drive data: How many passes are needed?


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