What is the difference between a 24-pin and a 20-pin motherboard power connector?

Related Model ( 2068 )

The 20-pin connector belongs to older ATX standard while 24-pin connector follows newer ATX standard. The 24-pin connector just the 20-pin cable with 4 extra wires to provide extra current. As long as your power supply can provide sufficient power to the motherboard, you can still use 20-pin power supply. 
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