I am trying to help a friend solve an unusual problem were the DSL signal drops
 whenever a particular Win7 pc is booted up to join the network.

They have an ADB P.DG A4001N router/DSL modem.  They use it with an adapter for
 voip.  It also feeds a smart wi-fi TV.  They also have a small android tablet.
  All devices work fine (simultaneously), no problem.

But when they boot up their Win7 pc... using wi-fi, the DSL (and access to the
internet for all existing devices) just drops.  The Win7 pc is able to
join/login to the ADB router device fine, but fails to get internet access.

The DSL recovers after a few minutes after the Win7 pc has been turned off.

I tried connecting the Win7 pc directly via ethernet cable, and the same
problem happens!

The Win7 pc TCP/IP is configured with "Obtain IP address automatically" and
"Obtain DNS server automatically".   The TV seems to prefer to always use
192.168.1.103.  The gateway/router is 192.168.1.1.

When I introduce my modest XP Thinkpad T60 via wi-fi (which is also configured
with "Obtain IP address.. Obtain DNS server.. automatically) I get a succesful
connection to the network/internet and the TV and tablet have internet access
fine.

But as soon as the Win7 pc is fired up and "connects" to the ADB, the whole DSL
 feed drops for everyone.

Any ideas on what would be causing this problem?

Meanwhile, I configured the Win7 pc to use a specific IP address and the
required gateway address.. but I haven't had a chance to test the pc on their
home network.

...AA

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