Networking MAJOR problems need help.

[one244]

I recently hardwired a new computer to a router that had two computers already in it. When the new one is plugged in the main comp slows down so slow its almost impossible to perform an online task. And, honestly the connection has slowed down a large amount on the other computers to. Any suggestions?

 

[Nodsu]

The new computer is riddled with spyware that hogs your connection?

 

[Samstoned]

could be a nic card setting
if your running xp try enabling netbios
it is not used in xp by default