Asus M2N4-SLI - Manual (Page 41)

ASUS M2N4-SLI 2-21
3. Keyboard power (3-pin KBPWR)
This jumper allows you to enable or disable the keyboard wake-up
feature. Set this jumper to pins 2-3 (+5VSB) if you wish to wake up
the computer when you press a key on the keyboard (the default
value is [Disabled]). This feature requires an ATX power supply that
can supply at least 1A on the +5VSB lead, and a corresponding
setting in the BIOS (see section 2.5.5 APM Configuration).
R
M2N4-SLI
M2N4-SLI Keyboard Power Setting
(Default)
+5V +5VSB
KBPWR
2 3 1 2