Power supplies following ATX12V 2.x standard – i.e., the power supplies you will find on the market today – use a 24-pin connector. So if your motherboard uses the ATX12V 1.x standard – i.e., it uses a 20-pin power connector – you will need to transform the main power connector from your power supply from 24-pin to 20-pin. This can be done through the use of an adapter that comes with the power supply or by removing the four extra pins, which was the case of our power supply.

Since our motherboard was an old one using a 20-pin connector, we needed to transform the power supply 24-pin connector into a 20-pin one, as shown in Figure 24. The mechanism used on your power supply may be different.

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Figure 24: Transforming the main 24-pin connector into a 20-pin one.

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Figure 25: The main power connector has now 20 pins.

Of course if your motherboard uses a 24-pin connector you don’t need to do this.

Now connect the main power supply connector to the motherboard, as shown in Figure 26.

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Figure 26: Installing the main power connector on the motherboard.

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Figure 27: Motherboard power connectors correctly installed.