The chipset does not support the RAID migration you are trying to do. This link will show you the migrations that are supported by ICH10R http://www.intel.com/support/chipsets/imsm/sb/CS-020674.htm
With the configuration you currently have in your system which is a RAID 0 volume of 3 Hard Drives you can only migrate to the following two RAID volumes:
- From 3-drive RAID 0 to 4-drive RAID 5
- From 3-drive RAID 0 to 5 or 6-drive RAID 5
If you want to have a RAID 10 volume it is necessary to create the RAID 10 volume from scratch.