Then you have to buy another cable to plug in.
Branded PCs should give you the discs, did you check the box that
comes with the PC? They always chuck it somewhere or they put it in
smaller boxes.
If it isn't there, call up the customer service centre and request
for a copy. Ask for the original discs, don't get recovery discs.
Recovery discs take up a lot of unnecessary space and bundle a lot
of useless programs.