Nvidia NFORCE 680I - Manual (Page 26)

8-pin ATX 12V Power (PWR2)
PWR2 is the 8-pin ATX 12V power connector used to provide power to the CPU. Align the
pins to the connector and press firmly until seated.
It is strongly recommended that you use an 8-pin ATX
12V power supply; however, if you have a four-pin power
supply, plug the connector to pins 1, 2, 5, and 6 as shown.
Auxiliary Power for Graphics (PWR3)
The PWR3 connector is an auxiliary power connection for graphics cards. Exclusive
power for the graphics card provides better graphics performance.
17
Hardware Installation
12V
5 1
8 4
GND
Back Panel
connector edge
5 1
Connect a four-pin
power plug to pins
1, 2, 5, and 6