Help a Freshman College Student

ziggsta · #1 (**permalink**) 30-08-2007, 11:26 AM

Ok i have a 500gb External hard drive every thing is running ok except for one thing. I was using partition magic so that i could chunk up the hard drive so that i could run a dual boot system windows and linux. Well in the middle of the process of making that partition Partition magic froze and i used ctrl alt delete to end the program. Well then sadly enough the hard drive wouldnt come up any more in my computer no big deal... so i formated it through admin tools and every thing was good.......

Untill i reallized my hardrive is saying that it is about 35 gigs less that what it actually is.........how can this be there is nothing on this hardrive anymore unless all of my old stufff is secretley still on there I tried to defrag but it did nothing. I need your help maybe i can get all my usefull school stuff back.

Dan Penny · #2 (**permalink**) 30-08-2007, 12:47 PM

A 500GB hard disk, once formatted, will end up being approximately 488GB. Is this what you are getting? Or are you getting 453GB? Disk manufacturers usually calculate a MB as 1000KB whereas it's actually 1024KB.

If you're running XP, go to Start, Run, and type in diskmgmt.msc. This should show you any installed hard disks/partitions.

ziggsta · #3 (**permalink**) 30-08-2007, 12:49 PM

it is coming up 476 gig

Digerati · #4 (**permalink**) 30-08-2007, 02:37 PM

To expand on Dan's line of thought, the problem is the way humans think. We think 1Kb = 1000bytes, 1Mb = 1000Kb and 1Gb is 1000Mb and so on. That's because we think in Base10. But that's not the way it is. Computers think in Base2 - that is to a computer, there can be only two states, on or off, 1 or 0, high or low. And so to a computer a kilobyte is 2 to the 10th power or 2 X 2 X 2 X 2 X 2 X 2 X 2 X 2 X 2 X 2 = 1024 bytes = 1Kb.

This is why RAM comes in 128Mb (2 to the 7th power), 256Mb (2 to the 8th), 512Mb (2 to 9th), 1Gb (2 to the 10th), 2Gb (2 to the 11th).

What makes it confusing is HD makers long ago decided they can make their HDs "sound" bigger if they label their drives the way humans think. To figure out the true capacity of an HD, divide the stated size by 1.024 - so 500 / 1.024 = 488.28 raw disk space.

But then after you partition and format, more disk space is consumed because all that formatted disk space (track and sectors) and partition mapping information must be managed and stored some where - and that space becomes unavailable.

A general rule of thumb is up to 7% can be consumed during formatting and partitioning. So, 500 X .93 = 465 which means your 476 looks fine.

ziggsta · #5 (**permalink**) 30-08-2007, 08:03 PM

Im really surprised on the awnser but im glad to know that its not broken is there any way i can get the 30 or so gigs back just like when i bought it?

Digerati · #6 (**permalink**) 30-08-2007, 09:42 PM

Huh? It is apparent you did not follow what we said. You did not lose it. The number of "bytes" on the disk has not changed. Some of the "discrepancy" (for lack of a better term) is due to what Windows calls a 1000 Megabytes and what the drive makers call 1000 Megabytes. The drive makers call 1,000 Megabytes a Gigabyte, Windows (correctly) calls 1024 Megabytes a Gigabyte. You consume exactly the same amount of gas traveling between New York City and Washington DC, whether you say you went 204 miles or 328 kilometers.

The rest of the so called "missing" space is used for file allocation and partition tables - the table of contents and indexes used to keep track of all the storage locations the drive and the operating system will use to store the file segments of your data and applications. Like the Table of Contents and Index of a book, they consume pages, but are not part of the story.

Note there are unformat utilities that do just that, they unformat the drive, after which you may see the full 500Mb. But of course, an unformatted drive is unusable - but it makes a nice paperweight.

ziggsta · #7 (**permalink**) 30-08-2007, 11:42 PM

My apologies for the ignorance I appreciate your guys thank you very much

Digerati · #8 (**permalink**) 31-08-2007, 12:23 AM

No need to apologize - remember the stupid question is the one not asked.