Erm get it via NTL officially and they will install it for you but you may not need a second STB to be able to view your feed on your PC. You might be able to split the feed and connect it that way.
NTL won't install a connection to a PC though, you would still have to do that bit so you may want to ask about splitting the feed correctly. Asking in the NTL tv area or the computing area might be better than posting here
