Power led question 2 pin vs 3 pin.

I have a question what the difference between the 3 pin power led connector and the 2 power led connector is. I know like most would need a 2 pin but what difference would a 3 pin make and what is it used for (what will the wires with 3 pins make in difference)? Is it for cases that have color changing leds? Thanks.

Older motherboards used the three pin connector. Modern motherboards need the two pin connector. If you have an old case, one thing you can do separate the leads.

Cut through the empty socket, then carefully sand the cut sides down, until you have two, square, separated leads.