Correct. You can refer below article from Microsoft for more details [URL] 
Hello! I have PE T310, server, BIOS version 1.14, with PERC 6/i RAID card. Initially it was installed with 4x500GB drives, hotswap. So I decided to give it more space and bought 4 2TB drives and put then into the system. I did RAID 5 setup, utility sees all of them, but finally after RAID initialization only 2TB is available for virtual disk and I realized that initial set of 4 by 500GB was not taken by occasion.   What can I do to make virtual disk to be 6TB? Thanks!   [IMAGE][IMAGE][IMAGE]
Poweredge T310 virtual arrays size limitations