I understand that black is negative and red is positive but what about when the wires are orange/white or blue/white. Is the lighter color(white) the positive one?
I have a thermaltake armor case with buttons/leds connectors that connect to the motherboard.
Looking at the red/black connector, the red connector side has an arrow shape on it. Considering red is positive I'm guessing the arrow shape means that the wire is positive.
On the color/white wires the color has the arrow shape so I'm going to go with peterhuang's suggestion.