Replacing black fan with LED fan:

Follow the two wires from the fan back to the circuit board, cut the wires off 3-4 inches from the circuit board and strip the wires back about ½ an inch (1cm). Unscrew the fan from its mounting point, and set it aside (you never know when you’ll need a fan).

Cut the wires on your LED fan about 3 inches from the fan (thus giving you a total of 6 inches of wire to play with).

If your LED fan has 3 wires, discard the yellow wire (RPM sensor) and take the red wire and the black wire and carefully solder them to the wires attached to the circuit board where you cut the old fan out.