NIC port problem

Hi All

I have a desk pc running win xp , which works fine opeing files etc.
But as soon as it is plugged into the network port the whole machine
comes to a grinding halt. This is a basic workgroup network over a ADSL
router.
When the laptop is plugged into the same port all is ok, so the problem
is on the desktop pc. Is it a bad nic and what can I use to test for
bad packets,error packets etc. Or what else can it be. Help will be
appreciated.

Thanks all

Spiff

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