Is this the board you're referring to? That's the first google hit for "ht2000"http://www.ecs.com.tw/ECSWebSite/Product/Product_Detail.aspx?CategoryID=1&DetailID=685&DetailName=Feature&MenuID=24&LanID=9
I can't see a clear HD image but it's probably one of the headers in the bottom right hand corner. Look for 'f_panel' or something like it written near a set of pins. If you mean you have this but don't know which of the pins is which, the best I can say if you can't find the motherboard manual is to play by trial and error. First find the pins that start the board (you can safely use a flat-head screwdriver to jump them, just be careful where you point the thing
) then figure out which ones go to which LED. Some boards label the individual connections but not all.
It can be a pain in the ass, I know!