here's the user manual and if you have not read it thorough pls do so.
http://anon.comcastonline2.speedera.net.staging.speedera.net/anon.comcastonline2/support/help/manuals/motorola_sb5100.pdfmore drivers and user manual downloads here
http://www.comcast.com/Support/Corp1/FAQ/FaqDetail_2427.htmlran thru your situation and so summarize:-
motorola SB5100 is a cable modem cum router can allows 2 pcs to be connected to the USB and ethernet port and surf at the same time.
your old PC connected to USB port of modem and u r trying to connect new PC to the ethernet port and use both connection to access the inetrent all at once.
really hope can take a look at your PCs and see what's going on.
I have a telephone modem and can work with 2 connections wonder why yours can't. pls go through the details of the user manual again and look out for all cable types, interference, drivers install, IP config (modem and local machines) etc.
or else best call starhub 24hrs technical support they can work it out on your conenction status right off their computers at their signal traffic centre and offer solutions. if they can't help you, most probably its modem functionality or compatiblility related. is this SB5100 modem bundled with your subscription plan?
i am glad the router i bought on my own works with my ISP and different processor type comp
