Yamaha DTXpress/DTXplorer/DTXtreme

hello all,
             i just got a 8 pin mini din cable for my module, to hook 
it up to my midi interface on my computer,now in the manual they show 
3 different types of cables which i will list for reference to my 
question i have .. first off they have the 8 pin to 8 pin mini din 
cable (for mac) then theres the 8 pin mini din to d-sub 25 pin(for pc-
1) then there is the 8 pin mini din to sub 9 pin (for pc2) ,but on my 
interface on my pc i have a 15 pin midi port (aka my game periferal 
port) now if i get an adapter for this cable to make it a 15 pin end 
what would i set the module switch to on the back of it 
(ex.mac,pc1,pc2,or midi) and if i just go get an adapter for the one 
end that wont work on my system,will it work this way or do i have to 
actually get the cable that is allready this way?????

any replies would be greatly appreciated