Asus DSBV-D - Manual (Page 118)

-1 Chapter 5: RAID configuration
Press again, the logical drive information appears including a Logical
Drive menu that allows you to change the logical drive parameters.
6. Select RAID from the Logical Drive menu, then press .
7. Select RAID 10 from the menu, then press .
You need at least four identical hard disk drives when creating a RAID 10 set.
8. Select DWC from the Logical Drive menu, then press .
9. Select On to enable the Disk Write Cache setting, then press .