Cn1 And Cn2 Atx Power Supply Connectors - American Megatrends Olympus III User Manual

Step 5 Attach Internal Cables,

CN1 and CN2 ATX Power Supply Connectors

Attach the power cables from the power supply to the connectors located at CN1 and
CN2. The socket is keyed so that the ATX power supply connector can only mount one
way.
Note:
Do not use a standard ATX power supply. The Olympus III motherboard will not boot
with a standard ATX power supply. Use only ATX12V-compliant or Server System
Infrastructure (SSI) Entry-Level Power Supply (EPS) EPS12V power supplies with the
Olympus III motherboard. ATX12V and EPS12V power supplies have an additional
power lead that provides required supplemental power for the Intel Pentium 4 processor.
The Olympus III motherboard will not boot if the ATX12V power supply is not
connected to both the CN1 4-pin (or 8-pin) and CN2 20-pin (or 24-pin) power
connectors.
For more information on ATX12V power supplies, see the formfactor.org website.
For more information on SSI EPS12V power supplies, see the ssiforum.org website.
The main power connector pinout is:
Pin
1
2
3
4
5
6
7
8
9
10
11
12
American Megatrends, Inc., Olympus III User's Guide (Series 875)
28
Continued
CN1
CN2
Signal Name
3.3 V
3.3 V
Ground
+5 V
Ground
+5 V
Ground
Power OK
5 VSB
+12 V
+12 V
+3.3 V
Pin Signal Name
13 3.3 V
14 -12 V
15 Ground
16 Power Supply On
17 Ground
18 Ground
19 Ground
20 -5 V
21 +5 V
22 +5 V
23 +5 V
24 GND
Cont'd