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Possible Duplicate:
Windows 7 taking more space than Vista?

Okey i recently installed windows 7 on my 500 gb hdd.

It says the the max capacity space of my HDD is 465, but it is actually 500gb

why is this?

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marked as duplicate by Snark, Ivo Flipse Mar 19 '10 at 23:07

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

Duplicate of… – Snark Mar 18 '10 at 9:12

A number of reasons:

  1. When disk manufacturers describe space they use Gigabyte = 1,000,000,000 bytes (109) but the OS (and everyone else) uses Gigabyte = 1073741824 bytes (230).

  2. The formatting of a disk uses some of the space (keep track of where files are, what space is free, ...)

  3. There is a hidden initial partition created by the Windows 7 installer (100MB) for the boot files.

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That's right. Calculation for you case confirms that: 500 * 1000000000 = 500000000000 / 1073741824 = 465,661. So points 2 and 3 are not even relevant here (they take space but it's not really noticable). Also it many laptops one can find recovery partition that holds copy of Windows installer and allows to recover laptop from system failure to the manufacture state. It may take up to 4 GB. – Sergiy Byelozyorov Mar 18 '10 at 9:31
Small FYI: As Richard had pointed out, disk manufacturers use the 1 gigabyte = 1000 megabyte. The OS uses the IEC units of 1 gibibyte (GiB) = 1024 mebibytes (MiB). Check out this Wikipedia article: – Isxek Mar 18 '10 at 15:10
as another small FYI, some computing professionals really dislike using the terms gibibyte and mebibyte to describe binary gigabyte and binary megabyte. we prefer to ignore the base-10 versions of these units entirely, except when necessary -- like when buying harddrives. – quack quixote Mar 19 '10 at 23:20