How to connect front LED, power switch, etc

[Souness]

I am having trouble connecting the pin connectors for the front leds and switches to my motherboard(DS3P). The manual states a particular orientation with regards to the positive and the negative sides of the pins, but i have no clue how to tell which end of the connector is positive and which is negative? Why is the simplist bit of the PC so complicated.

 

[Souness]

i have a lian-li PC-7 and i'm positive that i saw no + or - markers. any other way to tell? When looking down on the flat surface of the connector, with the wire cojming towardes you, is the +ve always on one side?
_____
|......| <- flat side
|......|
------
...| <-wire
...|
...|
...|

[ignore the dots]

 

[Souness]

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