Asus ESC4000/IB - Manual (Page 62)

4-8 Chapter 4: Motherboard information
7. RAID configuration utility selection (3-pin RAID_SEL1)
This jumper allows you to select the RAID configuration utility to use when
you create disk arrays. Place the jumper caps over pins 1–2 if you want to
use the LSI Logic Embedded SATA RAID Setup Utility (default); otherwise,
place the jumper caps to pins 2–3 to use the Intel® Matrix Storage Manager.