Inspiron 560 takes a while to get on the network.

Something is wrongl. Anyways this puter comes with Windows 7 x64.. and I have 2 of them. Both take forver to get "on the network".. I say this because you can set it with a static ip address and it doesnt matter.. The problem is they have mapped drives and they fail to connect because it takes forver to initialize... I wiped one clean and put on Windows XP and used the driver from dell.. Same thing! I have used the latest driver from Realtek website dated this month... Same thing.. I have tried a different switch... I have tried changing the network card settings from auto negotiate to 100Mb Full Duplex.. Same thing... I tried a gigabit port on the switch.. I tried a 100MB port on the switch... Can anyone think of anything I am over looking.. The only thing I can think of is perhaps this office is wired for 568A instead of 568B.. or AutoMDX isnt working if there is something odd about his cables.. Either way.. NONE of the other computers in the office are having these problems... I think its just a problem with these realtek nics...