I just purchased the Western Digital WD6400AAKS drive which is listed/sold as a 640GB hard drive. I installed it, then when in the Windows setup part where you create the partition, its shows a value of 618,xxx,xxxMB. Now in the past I've seen the number showing much lower that what appears in Windows so I thought it was a little strange but then remembered that much. Then, when I start Windows, when I right click the drive to format it, the formatting window shows 596GB I know in the past that the advertised/labeled capacity is slightly higher than what you actually get, but a loss of 40+GB?? That seems a bit excessive... This is the largest drive I have had yet since installing my '80GB' which broke down to 74.5GB total in Windows (XP), and I thought that was bad. Is this normal with drives this large? With ANY drives? Is there a way to maximize capacity? This could make a difference in my future plans