HD vs SSD storage capicity question

You know how hard drives aren't as big as they're supposed to be (ie 160 GB drives really only have about 148 GB of usable space)

Is it the same for SSDs? Will a 60GB SSD only show up as having 50 or so GB available?

 

It's not a space available issue - the space that isn't allocated to the user is being used up for formatting and paging purposes. It has nothing to do with the physical space that's actually on the drive. They do have the space they're advertised to have, it's just not all available to the user.

 

my 30 gig SSD has 29.8 gb total

 

Thanks for the explanation of why they don't match but that didn't really answer my question.

 

It depends on the vendor and the drive. E.g., OCZ's Core V1 drive was sold as 64GB; the updated Core V2 has the same amount of flash but is labelled as a 60GB drive. Both give you about 60GB of storage space; some of the rest is reserved for spare sector mapping etc.

 

Actually, it has nothing to do with "formatting and paging purposes" either.

Instead, it's an issue between binary and decimal. The box quotes the HDD space in decimal, where a gigabyte is a billion bytes. Windows quotes the space in binary, where a gigabyte is 2^30 bytes. That's why a 160 GB HDD is only 149 GBs. This will apply to any storage medium.

This question has been asked many times around here.

http://www.seagate.com/ww/v/index.j...toid=9493781e73d5d010VgnVCM100000dd04090aRCRD

 

I am looking at the OCZ Vertex 60GB and trying to decide if it's going to be enough.

 

Sorry, this is wrong.

It is in fact related to marketing in reality.

You see a gigabyte is actually 1,073,741,824 bytes.

However, in terms of marketing the product, they assume that 1 kilobyte is 1000 bytes (not 1024 as is the truth), 1 megabyte is 1000 kilobytes and so on. Therefore, applying the same maths, you would get the result that 1 gigabyte is 1,000,000,000 bytes.

So now do the math.

160 Gigabytes in marketing terms = 160,000,000,000 bytes.
160,000,000,000 bytes in actual Gigabytes = 149.012 Gigabytes.

Now they are not technically lying to us; it's all in relation to the conversion between different base numbers. But they are bordering on it.....

The same fact is true regardless of whether it is a HDD or a SSD.

This is true; again do the math:

30 Gigabytes = 30,000,000,000 bytes in marketing terms
30,000,000,000 bytes = 27.940 Gigabytes in actual terms.

Hope that helps.

 

So a 60gb drive will probably really have 54-56 gb. Windows 7 RC1 will take up 16GB of that, leaving between 38-40 GB for applications.

 

Exactly right,
it has nothing to do with marketing. You really get the capacity you buy, its just a difference between binary and decimal as Lithus mentioned.
This applies to everything from mechanical harddrives, SSD's and ramdisc's

K-TRON

 

Correct, a "60 Gigabyte" drive will actually have 55.879 Gigabytes available pre operating installation.

 

I'm sorry but it is to do with marketing. I do mention in my post that the difference is due to the usage of different base numbers, i.e binary and decimal, but if they chose to they could tell us the size that will actually be available according to the operating system.

My point is that they do not, because when selling a computer it does not look as good, and that my friend is marketing.

 

Thanks everyone. I think I can get away with getting the OCZ vertex 60GB. I have a 16 GB SDHC card for my documents so I think 55GB should be enough for the OS and all the applications I'll need.

 

Just so people aren't confused, GB is in the decimal system and means 10^9 = 1000^3, while the technical term for capacities in the binary system is GiB, which is 2^30 = 1024^3, which is why there is a discrepancy (almost 7% difference).

Mr. Moo said he gets 29.8GiB from a 30GB SSD. But if you work out 32GB in GiB, it equals 29.8GiB. So it depends on the company and how they label it. I guess OCZ is trying to be more "accurate" and they are trying to convey what is labeled is what you get on your computer. So while there is a technical aspect, there is also a marketing aspect (to make things seem bigger than they actually are).

 

so it's possible that ocz vertex 60GB is actually the same size as a 64GB drive from other companies. too bad we can't get all companies to stick with binary lol

 

My bad, didn't look to see that Mr.Moo had said it was 29.8GiB.

Yup, in fact if you look at the OCZ website; they offer SSDs in 32GB and 64GB flavours, so it's not that they are trying to be more honest, either Mr.Moo or whoever sold it to Mr.Moo didn't realise the capacity of the drive in binary terms.

 

Unlike HDDs, SSD drives are made with capacities of a power of 2, so you'll have 16, 32, 64, 128, and 256 GB drives.

 

how does intel get 80 and 160 then?

Thanks for all the help guys. I ordered a Vertex 60GB with 1 day shipping. Should have it by friday

 

The Intel SSDs are composed of 20x4GB or 20x8GB NAND chips.

 

The majority of OCZ's offerings are actually rounded down and are closer to the GiB values. As far as I know, every HDD and SSD uses base 10 (GB) values, with the exception of OCZ (though not the Samsung rebadges). So you will get about 7% less of the advertised capacity in every drive except OCZ's drives, which are pretty much what you get (~30, 60, 120, 250 GiB).

I think I read somewhere in the forum that the 80GB Intel drive has 77.6GiB when you load it up. So while most SSDs use a power of 2 in their capacity (like the Samsung 64GB drive, I think it's 60GiB), they still are in advertising in GB (decimal) and are not reflective of actual capacity in binary. Phew confusing!

 

I didn't say that SSDs don't use decimal, just that when building SSDs, they go for a power of 2 since SSDs are composed of NAND memory chips, which are built in powers of 2, unlike HDDs, that can use platters with "random" storage amounts, such as 250 GBs.

 

Just an FYI:

Source

I've had my venting thread on this issue in the past...my view on it now; I just ignore it.

 

The platter on HDD isn't actually exactly 250GB. Also.. sometimes manufacture use short stroking to make a drive with specific capcity. E.g. a 80GB hdd might have a single 160GB platter, but not all of the platter is used.

 

Ok, getting into a useless argument here. My point is that SSDs tend to stay with powers of 2, so a SSD marked 30 GB will actually be 32 GB, something marked 60 GB will be 64 GB, etc... Versus HDDs that have capacities that are not powers of 2.

 

While I understand with your statement, I'm just making a point that while SSDs use power of 2's for their capacities, this is NOT measured in binary (GiB). A 64GB SSD will show up in your computer as 60GiB. The exception was OCZ, whose label says 60GB (when they mean 60GiB), hence why they actually show up as that amount on your computer.

 

Sorry if I opened up a can of worms. The original question has been thoroughly answered

 

Heated debates often arise over minor discrepancies. The important thing is that you're satisfied you have an answer to your question.

And who said that size does not matter.......

 

Just to put it on the record, I never claimed that they were measured in binary. From my first post:

 

OCZ, Vertex series at least, 30 GB is advertised on the box and it's 30GB in Windows. 60GB is on the box, 60GB is available in Windows.

 

Alright, I mistook SSD capacities in power of 2's to be binary. Hope everything is clear to everyone.

edit: to Jlbrighbill, I already explained that OCZ is an exception to the rule of every other HDD/SSD manufacturer. I think we have beaten this topic to death, so moving on now...

 

I know but some people are still arguing it.

 

LOL, that sounds like you still want to fight about it. Calm down The post originator has gone away with an answer they are happy with. No need to continue battling away. Be cool

 

i have the OCZ vertex and it was listed as a 30 gig drive they were marketing it truely

 

My "64GB" Samsung SLC drive is really only 59.6GB or (64,020,803,504 Bytes [64 * 10^9 Bytes]). This is a standard decimal to binary conversion error and applies to both HDD and SSD.

The problem is related to marketing. To a drive manufacturer (possible exception of OCZ Vertex), a GB is 10^9 bits. However, to an OS developer or a RAM manufacturer, a GB is 2^30 bits. Hard drives have been marketed under the former for years, it's just that the extremely large hard drives available today make this error rather glaring.

 

some (like supertalent) started to specify the (rounded) value that you'll see in the os, too. a.k.a. if a 64gb disk formats to 59.6 (or what ever), they'll label it as 60gb. that way, users don't get that irritated.

it would be nice if hw vendors would write the capacity they get when just sticking in an os-disk, install it on the full disk, and read out whats there.

i mean, this is ridiculous, espencially for non-geeks.

but of course, hw vendors like the bigger numbers they can write on a disk. the current 1tb disks are actually 930gb or so, not? and the formatted 1.5tb one is 1.33 tb or so?

technically, windows would have to report it's numbers as Gibibytes, not Gigabytes. but this second naming (for binary modes) is imho more of a fix for something that could have been solved with just common sense before. why should an ordinary user understand the difference between a Gigabyte and a Gibibyte? (GB -> GiB). right: they shouldn't.

it's not like you buy one kg of sugar, to get home and notice in your kitchen it's measured 930grams of sugar only, as the sellers handle it differently. i mean.. no

but while some in the ssd marked now follow common sence and label it so that it looks the same in the os, most still don't. it would be great if ssd's by default ALL would label correctly would be another reason to support them.

espencially for small sizes, the loss of gb is a real loss (my 32gb ssd has only 29.something gb.. i'd like to have two more )

 

Once upon a time drives were labeled with both raw and formatted capacity. They should never have stopped that.

As for SSDs - it's natural to label them as 32GB / 64GB / whatever, because that's the real capacity of the flash chips. But again, that's the raw capacity, and it's also a fact that a portion of the capacity is reserved by the drive controller's firmware for spare sectors. So while there isn't the same kind of formatting overhead that magnetic drives have, there's still a difference between the amount of storage material actually in the drive, and the amount available for actual user data.

As a computer-savvy buyer, I expect to see SSDs labeled in binary units, since I know that's how the underlying technology is organized. I also expect the actual usable storage to be smaller, because I understand that a portion of the space is reserved. The end result is no different from the discrepancy in numbers that HDD vendors have been pushing for years. Just get used to it and move on...

And no, I don't want drives to be labeled with how much usable space will be on there after "an OS is installed" because it depends on the OS (and the choice of filesystem), and I'd be paying for them to invest the resources into arriving at a specification that probably has no relevance to me.

We're all adults here, we don't need to be spoon-fed everything. Give us the raw facts, and educate the consumers about the reasons for the observed differences. Educated consumers are the answer to the discrepancy.

 

Thank you. Finally someone who agrees with me that this is used as a marketing tool.

Could not agree more. It would be nice if they simply told us in GiB and had the OS have sizes in GiB. They'd lose a selling tool though, so I doubt it will happen.

Ah yes, back in the day. When you had to tell the BIOS how many cylinders etc your HDD had, and 1GB was unheard of, let alone 1TB

 

I knew this was going to be a painful thread to read haha!!!