Would be very suprised if it was Modem to be honest, for the price of them though you could probably just get one, I’ve got a spare adsl router you can have gratis if you want I’ve been using it for about 6 months and it’s ok.
Most problems lie in the fact most phone exchanges can’t actually give you 8 meg, e.g Birmingham the highest rated phone exchange in Birmingham is 4.3 meg. So to be honest unless it was NTL I would be supirised if you got more than that from your phone line.
pm me if you want the Router..hope this helps