Asus P5B - Manual (Page 54)

2-26 Chapter 2: Hardware information
14. Optical S/PDIF Out port. This port connects an external audio output device
via an optical S/PDIF cable.
15. Coaxial S/PDIF Out port. This port connects an external audio output device
via a coaxial S/PDIF cable.
16. PS/2 keyboard port (purple). This port is for a PS/2 keyboard.
• DO NOT insert a different connector to this port.
• DO NOT unplug the external Serial ATA box when a RAID 0 or JBOD is
configured.
• Before creating a RAID set using Serial ATA hard disks, make sure that you
have connected the Serial ATA signal cable and installed Serial ATA hard
disk drives; otherwise, you cannot enter the JMicron RAID utility and SATA
BIOS setup during POST.
• If you intend to create a RAID configuration using this connector, set the
JMicron Controller item in the BIOS to [RAID Mode]. See section 4.4.7
Onboard Device Configuration for details.