No.  The PERC's have a feature called "Online Capacity Expansion", which allows you to make your existing Virtual Disk (array) larger by ADDING a disk to it.  In OpenManage Server Administrator (OMSA) this is called a Reconfigure.  For example, you can reconfigure a 2-disk RAID 1 to a 3-disk RAID 5, expanding the VD's capacity by one disk's worth of space.  You can also reconfigure a 4-disk RAID 5 to a 5-disk RAID 5 by adding a disk, increasing your VD's capacity.  It was never intended to make your array bigger without adding a disk (swapping each drive out one at a time). What you can do now is configure a second VD using the unused space on those disks.  This will show up as a new "disk" in Windows Disk Management.  Because it is a physically separate disk, you will not be able to merge that space with space on the original partitions.   Unless you want to backup, create a new VD using the full disk space, and restore, you can create your second VD, create a new partition there, then copy the contents of your data partition on the first "disk" (assuming you have an OS partition - C: - and a data partition), delete the data partition, then expand C: using the partitioning tool of your choice (Windows Disk Managemen/DiskPart cannot do this in 2003), including a Server 2008/Vista/7 installation DVD.
I have two 75GB drives in raid 1. I was running out of space so I replaced one drive with a 500GB, re-initialized it, then swapped out the other 75GB with the other 500GB and reinitialized that as well. So I have two 500 GB in raid 1, everything boots up fine. Is there a way to resize the virtual disk to use the whole 500GB or am I stuck with the 75GB? This is on a Dell Poweredge 2950 Perc 5/i running firmware 5.2.2. I also have the Dell Server administrator software installed on the Windows Storage Server 2003 OS.
Perc 5/i - Resize Raid 1 virtual disk