You will need to partition and format the drive before it can be accessed as a separate drive letter.
If you are using Windows XP, Click Start -> Run
Type diskmgmt.msc and press Enter
Locate the newly installed drive (Disk 1, Disk 2 etc), right click and select New -> Partition. Follow the onscreen instructions to format the partition.
When completed, you will find the drive in My Computer as a separate drive
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You will need to partition and format the drive before it can be accessed as a separate drive letter.
If you are using Windows XP, Click Start -> Run
Type diskmgmt.msc and press Enter
Locate the newly installed drive (Disk 1, Disk 2 etc), right click and select New -> Partition. Follow the onscreen instructions to format the partition.
When completed, you will find the drive in My Computer as a separate drive
The following guide will provide more details:
http://www.webtechgeek.com/How-to-Partition-a-Hard-Drive-Windows-XP.htm
(scroll a little and goto the section Partition a Hard Drive in Windows XP..)