Originally posted by: sm8000
Actually, you've got what you can get. Every 160GB drive I've seen has come out to 149 in full. You always lose about 7%, hence 120GB drives will give you 111GB, and 160GB drives will give you 149.
Er, no. Your talking about the difference between GB and GiB.
HDD manufacturers state that 1 GB = 1,000,000,000 bytes. So a drive that's advertized as 160 GB is 160,000,000,000 bytes. Windows, on the other hand, uses 1 GB = 2^30 bytes = 1,073,741,824 bytes -- which is more accurately called 1 GiB (a giga-binary-byte or gibibyte).
160,000,000,000 bytes / 1,073,741,824 bytes per GiB = 149.01 GiB
It's also why you alternately see people discussing the "137 GB barrier" and the "128 GB barrier" or whatever.
We have 28-bit addressing of 512 byte standard sectors. 2^28 * 512 = 137,438,953,472 bytes maximum addressable HD size. So there's 137 GB, or:
2^28 * 512 bytes / 2^30 bytes per GiB = 512 / 4 = 128 GiB
We're dealing with the physically addressable locations, so with the overhead of partition tables and boot records, the cap is often known as the 127 GB barrier because you'll never see one at 128 GB.
So why can this guy see 131 GB? Seems kinda random, huh? That I'm not sure about, but I suspect there a BIOS issue to blame, or that Windows is confused by the BIOS's lack of support.
For reference 48-bit LBA mode also has a cap. But at 2^48 * 512 bytes, it's a cap of 128 PiB... 128 peta-binary-bytes.