VM (as ntl & Telewest) used to provide broadband via STBs
rather than cable modems in certain areas, but AFAIK do not do this anymore.
You need a cable modem, which I assume you already have.
And to connect your PC & PS3 at the same time, you need a router (well, you could use ICS, but it means leaving the PC on, & a router is just far better anyway).
Recommended router:
http://www.amazon.co.uk/Linksys-WRT5...6286128&sr=1-1
(many people here use it)