I have a Dell PowerEdge 2950 with four 500GB hard drives, Raid 5 leaving me
approx 1.5 T. The disk space usage is at 78%. What would be the most
efficient way to add a disk or two? Do I have to create another virtual
disk with the new drives or can I expand the current virtual disk?

Perc 5/I integrated BIOS Configuration Utility 1.02-007

SUSE Linux 10, running GWAVA Reload