ASROCK AD2550B-ITX Manual page 17

The front panel design may differ by chassis. A front panel module mainly
consists of power switch, reset switch, power LED, hard drive activity LED,
speaker and etc. When connecting your chassis front panel module to this
header, make sure the wire assignments and the pin assign-ments are
matched correctly.
Chassis Speaker Header
(4-pin SPEAKER 1)
(see p.2 No. 12)
Chassis Fan Connector
(3-pin CHA_FAN1)
(see p.2 No. 3)
CPU Fan Connector
(3-pin CPU_FAN1)
(see p.2 No. 1)
ATX Power Connector
(24-pin ATXPWR1)
(see p.2 No. 5)
Though this motherboard provides 24-pin ATX power connector,
it can still work if you adopt a traditional 20-pin ATX power supply.
To use the 20-pin ATX power supply, please plug your
power supply along with Pin 1 and Pin 13.
GND
+12V
CPU_FAN_SPEED
12 24
1 13
20-Pin ATX Power Supply Installation
ASRock AD2550B-ITX Motherboard
Please connect the chassis
speaker to this header.
Please connect the fan cable
to the fan connector and
match the black wire to the
ground pin.
Please connect the CPU fan
cable to the connector and
match the black wire to the
ground pin.
Please connect an ATX power
supply to this connector.
12
1
24
13
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