i have only recently become interested in assembling computers, however i encounteed a problem when reassembling one of my old computer's. The LED lights were not working, i think i ahve misconnected them to the motherboard, but im not sure where they should go.

Look closely at the jumper pins as they usually have the component connect name and position marked on the board. ie; hdd led power led etc. Hope this helps Mathew

If a led does not work when first connected, simply turn its connector around. Good Luck - Keep us posted.

To add a little trivia to response 2, a diode, or in this case a light emitting diode, is the most basic form of digital circuitry. It turns on (conducts current) when voltage is applied is one direction and stays off (does not conduct current) when voltage is applied in the opposite direction, or when no voltage is applied. It has two poles, positive and negative, aka a P-N junction. A transistor is just two diodes crammed together so that rather than having two poles, there are three, npn or pnp. This makes a transistor act as a type of boolean logic circuit, and why it is the basis for all digital circuitry. Not that anybody asked.