I'm trying to figure out why my blank CDs are showing up with different capacities in different drives. Both of the computers run Windows XP. My computer has a Sony DVD-RW DW-Q30A drive which shows the capacity of a blank CD as 576 MB, while my son's computer, with an older Sony CD-RW drive shows the capacity of the same disc as 702 MB. Is this typical or is there something wrong with my optical drive or something wrong in my OS that makes it report the wrong capacity when I look at the disc's properties? Any thoughts you have would be appreciated.