Asus P5MT-C - Manual (Page 117)

ASUS P5MT-C 5-23
6. Follow steps 6 to 7 of the Creating a RAID set: Using Easy
Configuration section.
7. Select Size from the Logical Drive menu, then press .
8. Key in the desired logical drive size, then press .
9. Follow steps 8 to 12 of the Creating a RAID set: Using Easy
Configuration section to add the new RAID configuration.