DHCP timed out error

I am running windows XP sp2, nortons anti virus, and have an nvidia active armour firewall. I will list the rest of my computer specs at the end.
My problem is that I am unable to connect to the internet and get a DHCP timed out error when I try to renew my ip.
I have tried to connect through two different routers.. One my room mates computer will connect through the other it wont, and I tried connecting it straight to the jack in the wall, which also doesnt work. I have also tried to connect it to my friends router across the hall which also doesnt work, all give me the same error.
The router I am currently using also doesnt allow my xbox to go on live either, and the network I am on requires the use of "PuTTY" But it does work if i use the cable from my friends router in the other room (both computers were authenticated)
Iv asked the comp techs here.. but they are very little help.. and unwilling to help because it is something on my computer not the network.

Oh the computer worked on my home network but not the university here


The computer I am trying to connect to the internet is :
3500+ Amd cpu
asus an8-sli mobo (it has 2 build in ghrz ethernet connections)
corsair 512 platnium pc3200 (x2) ramm
WD 160gig HD
nec dvd burner (donno the modle # I will figure it out if it matters)
evga 7800gtx Gpu
ocz powerstream 520watt power supply

If any info is needed on anything I will find it..
I have tried the things that other people have posted on this board about DHCP timed out errors and none seem to work..

I am able to authenticate PuTTY right after I restart my computer if I do it within the first couple seconds.. But I am not able to use the internet and PuTTY quickly becomes inactive after
I have tried to open all the ports putty uses, turn on my firewalls, change bios relating to my ethernet connects.. nothing has helped other then changing the error message from cannot contact host to DHCP timed out..

Thank you for reading this, and any help is greatly appreciated