Disk space lost after formatting!

I used the disk management tool in windows vista to reformat my partitions . After formatting and managing the partitions I found that the total disk space of the hard disk became 298 GB although that I am using Western Digital HD 320 GB. I tried to reinstall the windows again but no change even when I tried to install the system from the boot cd it reads the HD space 298 GB . I went to the BIOS and checked it I found that In the BIOS the HD space is readen correctly (320GB).. Is there any way to make the system read the actual space of the HD .
I was thinking about deleting all tha partitions and recreating them again if this may help ?

Operating system: Windows Vista Home Basic 32-bit
Processor AMD X2 2.6 GHz Dual core 64-bit
RAM 2 GB

Windows will always show less than the manufacturer due to a PC only understands binary, 0’s and 1’s, and that’s how Windows calculates your hard drive size. This means that an 320 GB drive, figured using the decimal 10 system, would only show as about 298GBs in Windows.

2^30=1073741824 bytes (1 binary gigabyte) what OS reports
10^9=1000000000 bytes (1 decimal gigabyte) what manufacturers advertise

320*1000000000=X*1073741824
X=320*1000000000/1073741824
X=298.023224
so 320 Gigabytes decimal (manufacturers claim) = 298 Gigabytes binary (reported by OS)


.

Thanks alot jephree.
I already found your answer very helpful

No problem.

Let us know if we can help further.