Loss of drive-space when installed?

[Llhweiir]

I have just installed my new SAMSUNG 250 GB harddrive. It was detected in BIOS, but not in Windows, so I used Acronis True Image to install the drive. However, Acronis detected only 232 GB of unassained space on the drive. That is 18 GB less that it is supposed to be.

I have never added a new drive before on any of my systems... Is this kind of "space-loss" normal?

[Buffalo2102]

Yes, it's normal.

It comes back to the difference between binary and decimal maths.  Computers work in binary where a byte-1024bits, a KB=1024bytes, a MB=1024Kilobytes and a GB=1024MB.  However, since we humans work in decimal, the drive manufacturers report drive capacities in decimal where a byte=1000bits, etc, etc, ....GB=1000MB.

In your case, a 250GB hard drive is 250,000,000,000bytes.  The computer actually sees that as much less space - 231,564,544,000bytes because there are 24 more bits to every byte in binary.  There are also some losses due to formatting and the OS will round off the final value but that's about it.  Personally, I see this question come up a lot and I think it's about time that the drive manufacturers started reporting capacities in both binary and decimal values.  It isn't rocket science for them to work out and it would only be a small addition to the drive label.

Buff