I've read various recommendation configurations. Probably best for the voice side if your WRTU54G-TM is the first device connected to the cable modem. However it's also been suggested that you can use another router in between and split the traffic: part to your WRTU54G, servicing only the phones, and part to another router that services your PC's. Not sure how much difference that would make, but if you have an extra device it might be worth the experiment.