Look on the lower right of the motherboard , for a row of about ten pins. Look closely and you should see p+, p-, Hd led, reset and pwr or something like that. You might need a magnifying glass in order to see the letters. Might be a grd also, this would be a (-)
One side of the row of pins should be all the positive side (+) and the other side, negative (-),
so if you can see one +, then that side will be the plus side. I
The row of pins is made up of two pins per row, so there should be five sets of two pins each
The -p led would be across from the +p led and is the light for the power on the front of the case.
The Hdd is the Hdd light, which is also on the front of the case. And the Reset PW is for the Reset button on the front, a smaller button that you use to do a warm reset.