Large Discrecpency In Storage Space

[JamesAllen]

My PC is not yet complete, and so far only has the SSD boot/app drive installed as storage (no HDD yet). It is a 60G drive. I have a few questions after installing it and my some drivers.

1.) It appears as a 55.7G drive on the OS. I know drives always show smaller than their maximum memory due to space allocated for formatting, but a drop over 4G seems like a lot. Why is that?

[strike]2.) After installing all of my hardware and MoBo drivers, I have 33.2G remaining (meaning I have used 22.5G of the original 55.7G available according to the Win7). This seems like a lot of space used without anything but the OS and drivers actually installed. I have yet to even update Win 7 which I understand will add quite a bit more data to the drive. After looking at the individual folders with all hidden folders visible, they only add to 12.14G space on drive. Where are the other 10.36G coming from?

* I have already allocated the lowest possible amount to system restore, and have removed all but the latest system restore point so this is no the issue.[/strike]

I disabled hibernation and gained much of the disk space back (only 8.5G in use from the 55.7G capacity). I still was wondering about question one though.

Thank you

 

[Ubrales]

Here is what I read about it:

Many people notice missing space right when they open the box. They bought a system with a 160GB hard drive, but Windows shows the total drive capacity as 149GB. That's a difference of 11GB right off the bat. The reason for this has to do with how you measure capacity to begin with. We measure bytes using progressively larger sizes, starting with K (kilobytes), M (megabytes), G (gigabytes), each one standing for a multiple of 1000. So 1K = 1,000, 1M = 1,000,000 (1000 * 1000), and 1G = 1,000,000,000 (1000 * 1000 * 1000). These are the units that companies use when they advertise the size of their disks, so your 160GB drive is 160,000,000,000 bytes in these measurements.

However, computers are binary systems, and measuring in multiples of 1000 isn't the way they do things. The closest thing we have in binary is 1024. So, for a computer, 1K = 1,024, 1M = 1,048,576 (1024 * 1024), and 1G = 1,073,741,824 (1024 * 1024 * 1024). As a result of this, a computer thinks that 1GB is bigger than what a person typically refers to as 1GB (a difference of 73,741,824 bytes). If we take our example of a disk that's advertised as 160GB, and divide by what a computer thinks is 1GB, we wind up with: 160,000,000,000 / 1,073,741,824 = 149.012, which is what Windows says is the drive capacity.

This measurement makes it seem like the drive is smaller, which is the reason I call this "marketing". Everyone wants to make their drives seem bigger, so they use the larger number, even if it's not exactly accurate.

Because of this confusion, new standards of measurement have been devised to help clear this up. Officially, the term "megabyte" refers to 1,000,000 bytes (1000 * 1000), and the term "mebibyte" refers to 1,048,576 bytes (1024 * 1024). The abbreviation for "megabyte" is "MB", like you're used to, and for a "mebibyte" it's "MiB". Notice the "i" in there. It's subtle, but important to make the distinction. You probably won't see these units in use by large companies for a while, but it's something you should be aware of anyway. See mebibyte for more information.

Here's a table comparing the "marketing" size vs. the computer size for some typical drive sizes:
Typical drive sizes
Marketing Computer
80 GB 74.51 GiB
100 GB 93.13 GiB
120 GB 111.76 GiB
140 GB 130.39 GiB
160 GB 149.01 GiB
200 GB 186.26 GiB
250 GB 232.83 GiB
300 GB 279.39 GiB
320 GB 298.02 GiB
350 GB 325.96 GiB
400 GB 372.53 GiB

 

[JamesAllen]

Best answer selected by JamesAllen.

 

[Ubrales]

Thank you!