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Disk Management Only Showing 596.17GB of 640gb HDD
wahjahka
i have a 1 TB HDD that i currently use for xp pro, and i have 2 WD 640gb HDD that will be used for win 7, however when i open up disk management it shows both drives with only 596.16GB of space....why?!?
any help to solve my question will be great thanks.
any help to solve my question will be great thanks.
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More about disk management showing 17gb 640gb

I believe that is all the space that you can get out of those drives. Typically manufacturers advertise more than what is actually available on hard drives. I really don't understand why, but that's what they do. For example, my 300GB velociraptor is advertised as 300GB, but in reality it's capacity is 270GB. I have two 500GB drives, but they only can hold 465GB each. Basically, it's just how it works.

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It's called "marketing" .... since computing in 1's and 0's is a base 2 thing , a GB = 1024 MB (2^10th power). But the marketing whores quickly recognized that they could falsely imply that HD's were bigger than they are but using 1 GB  1,000 MB
See http://en.wikipedia.org/wiki/Gigabyte 
JackNaylorPE said:It's called "marketing" .... since computing in 1's and 0's is a base 2 thing , a GB = 1024 MB (2^10th power). But the marketing whores quickly recognized that they could falsely imply that HD's were bigger than they are but using 1 GB  1,000 MB
See http://en.wikipedia.org/wiki/Gigabyte
I would say that the hard drive manufacturers are right on this one, and the OS system of measurement is screwed up.
A kilometer is 1000 meters
A kilogram is 1000 grams
A kilopascal is 1000 pascals
A kilowatt is 1000 watts
And yet somehow, a kilobyte is 1024 bytes?
Here's the difference:
A binary kilobyte (what the OS uses) is 1.024 decimal kilobytes
A binary megabyte is 1.0486 decimal megabytes
A binary gigabyte is 1.074 decimal gigabytes
A binary terabyte is 1.1 decimal terabytes
The OS measures in binary, while hard drive manufacturers measure in decimal. 596.16 binary GB * 1.074 = 640.3 decimal gigabytes (meaning that your drive has 640.3 billion physical bytes on it). 
I agree.
There are TWO reasons for the lower size:
1) Base10 versus Base2 as mentioned
2) Formatting the disk takes a small percentage
It's pretty accurate to take 93% of the advertised as the space left over after the conversion and formatting.
BTW, I agree with the decision to use Base10 to advertise. People understand Base 10 (i.e. a Gigabyte is 1000x a Megabyte). In the computer world we know that it's actually 1024. Giga and Mega are normally multiples of 1000 anyway, the fact that 1024 was so close to 1000 is why the names were chosen. People occasionally notice this discrepency, but I still think using normal Base10 for storage is the best way to go. 
BY the way, there is NO space lost because of this confusing use of the same word, "Gigabyte", for two different measurements of space. Windows uses the term to mean 1,073,741,824 bytes. But it also uses that same measurement system to tell you the size of each file, and the amount of empty Free Space, etc. If you had a file of exactly 6,400,000,000 bytes a Disk manufacturer would call it 6.4 GB and it would occupy exactly 1.0000% of your drive. But Windows will report that file's size as 5.960 GB and it still will occupy exactly 1.0000% of your drive.
Think of a meter stick, which is 39.370 inches long. Someone uses it to measure across your back yard and reports the distance using the full meter length, but tells you is is "64.09 sticks". Someone else does the same job but uses the inch marking instead and reports the result in actual yards, but still tells you the answer in "sticks", thinking since this is a "yardstick", you obviously wanted the work done in yards, not meters. You will get different numbers, but both people used the word "sticks" for the units of measurement. And in fact, your yard did NOT change size between the two measurements. 
cjl said:I would say that the hard drive manufacturers are right on this one, and the OS system of measurement is screwed up.
A kilometer is 1000 meters
A kilogram is 1000 grams
A kilopascal is 1000 pascals
A kilowatt is 1000 watts
And yet somehow, a kilobyte is 1024 bytes?
The first four are all base ten units of measurement, so the comparison doesn't carry over to base 2. Odd to think if we had 6 fingers we'd all be using base 12. 
JackNaylorPE said:The first four are all base ten units of measurement, so the comparison doesn't carry over to base 2. Odd to think if we had 6 fingers we'd all be using base 12.
The standard use of the prefix "kilo" is base 10 though. In SI, kilo means 10^3, and it doesn't change just because something else is more convenient.
(This has been corrected too  the technical term for the binary one is a kiB now, as opposed to the decimal kB, but it's kind of awkward and hasn't caught on) 
cjl said:I would say that the hard drive manufacturers are right on this one, and the OS system of measurement is screwed up.
You might call it screwed up but your computer operates on the principles of Base 2.
Going to Base 10 has always been a marketing factor.
There exists a sizable push by the computing community to change capacity and bandwidth measurements to their proper Base 2 units: Mebibyte, MiB; for example. 
TheViper said:You might call it screwed up but your computer operates on the principles of Base 2.
Going to Base 10 has always been a marketing factor.
There exists a sizable push by the computing community to change capacity and bandwidth measurements to their proper Base 2 units: Mebibyte, MiB; for example.
Just because the computer operates in base 2 doesn't make the binary units any more "proper" than base 10. They are quite simply measurements, and for the average user, base 10 is more easily understood. Because the base 10 units seem more natural to most people, they should be the ones used.
At least that's how I look at it... 
Base 10 might be more understood by the average joe , but the simple fact is that computers don't run on base 10. The technical terms need not be dumbed down accordingly. Back in the day when programmers and hardware geeks ran things, this base 10 stuff was non existent. I remember buying a 1 GB HD in 1993 for $1,000 and back then no one was going on forums asking why they weren't getting their full HD capacity.
Only when sizes started getting bigger and bean counters and marketing bumpkins started sitting in the corner offices instead of the programmers and hardware geeks did we see this base 10 stuff start to creep into the industry.
The question you have to ask if you're going to take the average joe position is .....does 2 GB of RAM get you 2,000 or 2048 MB ? Why hasn't RAM followed this base 10 stuff ? Simply cause 2.048 has no marketing value. 
It's not a matter of what computers run on though. The prefixes are standard metric prefixes, and in all cases, are defined as base 10. Just because somebody decided that 1024 is close enough to 1000 to call them the same thing doesn't make 1024 the right value (even if it is more convenient for computers).
If they defined them with the MiB, GiB, etc, that would be fine. Those are different prefixes, and actually do mean the base 2 values. However, to claim that a 640GB drive is actually a 596GB drive (even though it legitimately has 640GB by the standard use of the prefix on it) is ludicrous. 
Simply put.....
There are 10 kinds of computer users in the world ...... those that understand binary and those that don't.
If you understand that comment, you understand why 1024 is correct.Quote:The prefixes are standard metric prefixes, and in all cases, are defined as base 10. Just because somebody decided that 1024 is close enough to 1000 to call them the same thing doesn't make 1024 the right value (even if it is more convenient for computers).
Apples and oranges .... Chinese and Apache ......talking different languages. Byte is a binary term, not base ten term.
A binary kilobyte is 1.024 decimal kilobytes
A binary megabyte is 1.0486 decimal megabytes
A binary gigabyte is 1.074 decimal gigabytes
A binary terabyte is 1.1 decimal terabytes
"There has been considerable confusion about the meanings of SI (or metric) prefixes used with the unit byte, especially concerning prefixes such as kilo (k or K) and mega (M) as shown in the chart Prefixes for bit and byte. Since computer memory is designed with binary logic, multiples are expressed in powers of 2, rather than 10. " 
JackNaylorPE said:Simply put.....
There are 10 kinds of computer users in the world ...... those that understand binary and those that don't.
If you understand that comment, you understand why 1024 is correct.Quote:The prefixes are standard metric prefixes, and in all cases, are defined as base 10. Just because somebody decided that 1024 is close enough to 1000 to call them the same thing doesn't make 1024 the right value (even if it is more convenient for computers).
Apples and oranges .... Chinese and Apache ......talking different languages. Byte is a binary term, not base ten term.
A binary kilobyte is 1.024 decimal kilobytes
A binary megabyte is 1.0486 decimal megabytes
A binary gigabyte is 1.074 decimal gigabytes
A binary terabyte is 1.1 decimal terabytes
"There has been considerable confusion about the meanings of SI (or metric) prefixes used with the unit byte, especially concerning prefixes such as kilo (k or K) and mega (M) as shown in the chart Prefixes for bit and byte. Since computer memory is designed with binary logic, multiples are expressed in powers of 2, rather than 10. "
Believe me, I understand binary. I also understand SI prefixes, apparently unlike most people here.
It doesn't matter what is most convenient for a specific system. The prefixes are defined quite specifically. If you put "kilo" in front of a unit, it multiplies it by 1000. "Mega" multiplies by 10^6. Even if your system naturally falls into base 29, kilo will still mean 10^3. Always. This is part of the point of the metric system  to eliminate the different bases that were previously used and standardize everything to base 10 (regardless of what that was originally in).
The only reason why it was used as 2^10 was sheer laziness. People assumed it was close enough to the correct value that it didn't matter. The problem with this assumption is that with each successive multiple of 1000, the "estimation" gets farther and farther off, and it's up to 10% error when you have a capacity of several terabytes. This is why the binary prefixes were invented. 2^10 bytes is precisely 1 kiB, or 1.024 kB. This is a fact, and convenience is irrelevant. 
It has nothing to do with convenience, my quote is a dictionary definition. I binary kilobyte is and always will be defined as 1024 MB 1.024 or decimal kilobytes. Dropping the modifier "binary" for convenience does not auto substitute a different modifier "decimal".
Putting "kilo" in front of a chinese word will make no sense as it's in a different language. Same thing just cause kilo means 1,000 in base 10 (decimal) language doesn't mean kilo means the same thing in base 2 (binary) language.....
Why does 2 GB of RAM = 2048 MB .... why does 1 GB of graphics memory mean 1024 MB .... why is everything else that ahs ever been said about compuers use 1024 and ONLY HD manufacturers uses 1,000 ?
Better yet why do my 1 GB SCSI drives which I bought in 1993 contain 1024 MB or does this kilo thing only apply in this millenium ? 
JackNaylorPE said:It has nothing to do with convenience, my quote is a dictionary definition. I binary kilobyte is and always will be defined as 1024 MB 1.024 or decimal kilobytes. Dropping the modifier "binary" for convenience does not auto substitute a different modifier "decimal".
Actually, it does. Binary kilobyte is actually a (technically incorrect) way of saying "Kebibye" (the proper term). Kilo means (and has always meant) base 10.JackNaylorPE said:
Putting "kilo" in front of a chinese word will make no sense as it's in a different language. Same thing just cause kilo means 1,000 in base 10 (decimal) language doesn't mean kilo means the same thing in base 2 (binary) language.....
Kilo is a standardized prefix. It does always mean the same thing. Specifically, it means that whatever comes after it is multiplied by 10^3.JackNaylorPE said:
Why does 2 GB of RAM = 2048 MB .... why does 1 GB of graphics memory mean 1024 MB .... why is everything else that ahs ever been said about compuers use 1024 and ONLY HD manufacturers uses 1,000 ?
Better yet why do my 1 GB SCSI drives which I bought in 1993 contain 1024 MB or does this kilo thing only apply in this millenium ?
Technically, your 2GB RAM modules contain 2 GiB. They contain more than 2GB. Your 1GB SCSI drives contain 1GiB. Again, this is more than 1GB.
(2GiB=2.15GB, 1GiB=1.074 GB) 
cjl said:Technically, your 2GB RAM modules contain 2 GiB. They contain more than 2GB.
So again, why is the HD one way and every other component or software characterization of space on a computer the other way ?
Graphics Cards Use 1024
CPU cache uses 1024
RAM uses 1024
Windows uses 1024
Software footprints use 1024
So "technically" everything else is wrong and HD's are right ? 
Yep.
I'd be happier if everything was just marked in binary prefixes though (so your RAM would be 2GiB, your hard drive would be 596GiB, your video card would have 512MiB or 1GiB or however much it has, etc). I agree, binary is more sensible to use on a computer, but to use the decimal prefixes is incorrect.
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