NAS + 300GB HDD = 279GB Storage


Active Member
This wekend I installed a 300GB HDD ( ) into one of these:
It's working great and is easily shareable with all my machines and has its own ftp server. I essentially got an "almost' 300GB NAS for about $160 - not a bad deal at all.

However, once I installed teh 300GB disc and used the NAS case's format command, I ended up with only 279GB of space available. The case can only use FAT32 for its FS.

Now, when I map the drive and look at it in Windows, it says:

Capacity: 300,009,586,688 bytes, 279GB

I know there are different ways that folks use to calculate space on drives. The drive manufacturer is made by maxtor. I'm guessing they used the

"300 billion bytes is 300GB" logic,

rather than the

"300 billion bytes /1024 = 292978112 kilobytes /1024= 286111.4375 megabytes /1024 = 279GB" logic.

So who's right maxtor or my OS (winxp pro)? It's not right that there can be two different standards for reporting capacity.

Checking my other drives (a mix of seagate, maxtor and western digital) they're all in the same boat... Their "advertised" volume appears to be based on the number of bytes, not the literal meaning of gigabyte.

I think I've read about this over and over again. I guess, since this is the largest drive I've ever bought that it just seemed more "in my face" since I've actually "lost" more storage than one of my smaller drives (20GB) has all together - so it's the first time I really noticed.
It's been that way since whenever the drive manufacturers decided to count differently. You've just never noticed.

You may be losing some more room to space the NAS uses for itself (which may be in a separate partition).
Check Wiki... makes it nice and simple... M$ is really the culprit, eh?

There are three slightly different definitions of the size of a gigabyte in use:

1,000,000,000 bytes or 109 bytes is the decimal definition used in telecommunications (such as network speeds) and most computer storage manufacturers (such as hard disks and flash drives). This usage is compatible with SI. HP claims media makers Maxtor, Iomega and Western Digital adhere to using this amount.[1]

1,073,741,824 bytes, equal to 10243, or 230 bytes. This is the definition used for computer memory sizes, and most often used in computer engineering, computer science, and most aspects of computer operating systems. The IEC recommends that this unit should instead be called a gibibyte (abbreviated GiB), as it conflicts with SI units used for bus speeds and the like. HP states Microsoft normally adheres to this definition [1]

1,024,000,000 bytes, is the definition used by Hard Disk maker Seagate. [1]