JeremyHill said:
Yeah I didn't know how to describe it, but when I was reading about it online they said if you buy an SSD at 256 you don't get the full 256 cause part is being taken up by the SSDs programming or something. That sucks though that it takes up so much space =/
So can I run a system off an SSD? Like i don't need a backup at all? just one 256gig SSD and there's no greater risk of system failure or anything like that? I was always under the impression that SSDs are less stable, and more prone to corruption.
What you're talking about is the firmware. The controller firmware is usually quite tiny and is invisible to the system unless you're running a firmware updater (which is definitely something that you should do). The reason that Windows reports a different hard drive capacity than advertised on the box is due to a difference in measurement. Storage manufacturers consider 1 Gigabyte to be one billion bytes, expressed scientifically as 10^9 bytes . Everyone else in their right mind consider 1 Gigabyte to be 1073741824 or 2^30 bytes. One is measured in base 10 and one is measured in base 2. Accordingly, storage manufacturers consider 1 Terabyte to be 10^12 bytes but everyone else considers it to be 1099511627776 or 2^40. Working backwards we can see that 1 kilobyte is 10^3 bytes according to the manufacturers and 2^10 for everyone else and one megabyte is 10^6 bytes according to the manufacturers and 2^20 for everyone else.
By looking at the difference of the two we can see that an exactly 1 Terabyte (storage measurement) hard drive actually shows up as 1,000,000,000,000/1,099,511,627,776 = 909.49 Gigabytes (sane measurement). However, 1 Terabyte (storage measurement) is an extremely sharp number and not entirely reflective of the engineered capacity of the drive. The actual storage capacity is a multiple of a multiple of a multiple of 512 bytes. 512 bytes is the size of a sector on a hard drive and a sector is the elementary (indivisible) storage unit on a hard drive. Some new hard drives are using 4096 byte sectors but that's another topic. Thus, a 1TB drive actually has a little bit more than 1TB of space (Storage measurement) but not quite 1 TB of space (sane measurement) which is why it would appear to Windows as having a capacity of around 931GB. The exact same logic applies to SSDs in that the real capacity is just some multiple of some multiple of some multiple that can be expressed using two different bases (base 10 and base 2) and a common SI suffix to confuse customers.