Well I have a 128gb ssd in my z and I know 128 wont be available just like normal hard drives and all memory cards but in my intel rst it only shows the 2 drives as 60 and 60 and total of 119gb. Now is that normal? Thanks
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Yes, that's just the difference in calculations on what constitutes a GB. Same issue with all hard drives and SSD's.
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Remember part of your drive is reserved for a recovery partition which I believe is split away from the C drive. That's also a reason why you see less storage.
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^true but not the issue here. 128GB from a HDD mfr = 119GB according to any modern operating system.
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Achusaysblessyou eecs geek ftw :D
128GB in terms of the manufacturer: 128000000000 bytes / 2^30 (<-- because your computer works in binary) = ~119 GB to your computer
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For HDDs, the discrepancy is that most OS manufacturers use base 2, while HDD manufacturers use base 10 for consumer drives (for Enterprise drives, where they also use base 2).
The bigger the HD, the bigger that discrepancy is.
1 k (base 2) = 2^10 = 1024, a 2.4% discrepancy
1 M (base 2) = 2^20 = 1048576, a 4.9% discrepancy
1 G (base 2) = 2^30 = 1073741824, a 7.4% discrepancy
1 T (base 2) = 2^40 = 1099511627776, a 10% discrepancy
For SSDs, the same problem exists, BUT, in addition, another one. A certain portion of the drive is also set aside for wear leveling and bad block mapping, and isn't usable by the user, no matter how the drive is formatted. The unscrupulous manufacturers will count this space too, so a 128 GB SSD might actually only have 120 GB usable, before considering the base 2 / base 10 discrepancy.
In the case of the vaio Z, which uses fakeraid, you also lose a little bit because a small part of the drive has to be left unraided to contain the raid markers for each drive. Due to Sony not using GPT but MSDOS formatted drives, the RAID marker non-partitioned space has to start at an even multiple of the CHS "cylinder" information. So you lose a small chunk there too.
And yes, there's a recovery partition.
As well as the NTFS file system being used having a notoriously large file table, so you will never get anywhere close to the raw partition size once it's formatted.
All in all, never expect the advertised drive size to match usable space. It will be less. How much less depends on the manufacturer, the drive setup, as well as the OS and file system you use.
Vaio Z ssd 128gb not showing full capacity?
Discussion in 'VAIO / Sony' started by nyyankees3511, Apr 29, 2011.