[Rob]

Where the cable is taken from to the modem location will depend on the installer and the routing. It's more usual for the installers to add a splitter at your current internal cable isolator box, or even where your STB is located, than run another cable from the external wall box.

If you are a new broadband customer, you will always get a modem installation, not STB, even if you were in a STB enabled area. For all but the lowest speed services STB broadband has become obsolete, so Virgin Media are phasing it out. Certainly having moved to a modem a month ago, I've found my connection is much more stable than the STB ever was.