I have a Thermaltake Armor full tower case, and the PWRLED wire has a connector with 3 slots, but the motherboard only has 2 pins available for a power LED. The problem is that the wires from the LED go to slots 1 and 3, which means I'd need 3 pins on the motherboard, but I only have two available. Help? (By the way, I have an EVGA 780i SLI motherboard.) Thanks.

Just try all combinations until it works... it's bound to work!

The only pins left, though are those 2. I have, however, upon searching the rest of the internet, found people with same problem, and they said that you either have to remove the wires and move them around, or cut the connector in half. I just cut it in half, it should work now. Thanks, though!

Either split the cable so you can plug the two wires to the two pins on the motherboard, or get a plug made for the 2 wire setup and transfer the 2 wires to it.

Just pry the flanges up slightly on the connector, remove the pins and put them into the correct slots in the connector (and cut off the empty slot of the connector if necessary).

take a good sharp pair of scissors [without running lol] and cut the connector in half.
 
if the pins are next to one another face them together with the opposite ends that you didn't cut so they fit on the terminal block.