Special video card, and compatible software. Look at www.newegg.com for compatible video cards. Shouldn't be too much trouble. Just install the card, drivers, and software and you should just be able to connect through your regular cable connection.
You will proably have to get a splitter for your cable cord, since you can't have it going to your modem and your computer at the same time.
You will proably have to get a splitter for your cable cord, since you can't have it going to your modem and your computer at the same time.